manual chemistry 2014

RESTRICTED

RESTRICTED

! !!

PEPERIKSAAN SIJIL TINGGI PERSEKOLAHAN MALAYSIA

(MALAYSIA HIGHER SCHOOL CERTIFICATE EXAMINATION)

Manual for School-Based Assessment: Chemistry Practical

Paper 4 962/4

STPM 2014

REMINDER: This manual is specifically for the use of teachers or examiners only and should not be given to unauthorised persons. __________________________________________________________________________________

This SBA Manual consists of 83 printed pages.

Majlis Peperiksaan Malaysia 2013

MAJLIS PEPERIKSAAN MALAYSIA (MALAYSIAN EXAMINATIONS COUNCIL)

RESTRICTED

RESTRICTED

Contents

Page Part 1: of Chemistry Practical

1.1 Introduction 1

1.2 General Information 1

1.3 Recording of Assessment Marks 2

1.4 Moderation 3

1.5 Practical Work Assessment Guide 4

1.6 Project Assessment Guide 9

1.7 Summary of the Allocation of Mark for Each Experiment 16

1.8 Table of Summary of Experiment and Project 17

1.9 Preparation of Solutions 19

1.10 Guidelines for Experiments 22

1.11 List of Apparatus and Materials 36

Appendix A 49

Appendix B 50

Part 2: of Chemistry Practical

2.1 Introduction 51

2.2 Assessment of Practical Work and Project 51

2.3 Table of Summary of Experiment and Project 54

2.4 Experiment for First Term 56

2.5 Experiment for Second Term 66

2.6 Experiment for Third Term 75

RESTRICTED CHEMISTRY PRACTICAL STPM 2014

1 RESTRICTED

Part 1: Teacher's Manual of Chemistry Practical

1.1 Introduction 1.1.1 This manual contains administration and guidelines on the implementation and

assessment of the practical work and project which have to be carried out by the school. 1.1.2 Some of the skills that should be developed in STPM Chemistry subject (e.g. handling

of apparatus, observation, interpretation of results, and planning) can only be fully acquired through practical work and project.

1.1.3 Continuous assessment of practical work and project in school throughout form six will

ensure that direct assessment of all the desired practical and scientific skills of students can be made.

1.1.4 The practical science assessment is carried out in schools with the following objectives:

(a) To establish a practical work assessment system which is fair, accurate and comprehensive;

(b) To improve the practical skills and the quality of practical work of students;

(c) To inculcate independence, teamwork spirit, scientific attitudes and critical thinking among students.

1.2 General Information 1.2.1 The teacher in charge of the school-based assessment of practical chemistry will be

provided with a softcopy of the the administration of practical chemistry assessment, practical work assessment guide and description of experiments.

1.2.2 Malaysian Examinations Council (MEC) will provide a softcopy of Teacher's and

which can be downloaded from MEC Portal (http://www.mpm.edu.my) during the first term of form six. MEC will send username and password to Principal of the school for the downloaded purposes. The school is expected to make the duplicate copies of the Student's Manual which contain experiments to be given to each student.

1.2.3 MEC has determined 13 compulsory experiments and one project to be carried out

by students which will be assessed by the teacher in three respective terms. 1.2.4 Experiments and project are to be carried out either individually or in groups as

recommended in the Table of Summary of Experiments and Project on pages 17. 1.2.5 The teacher is expected to prepare the experiments according to this manual. MEC

should be informed of any modifications made by using the Experiment Report Form (See Appendix B on page 51)

1.2.6 The recommended time to complete the practical works report and project report is as

recommended in the Table of Summary of Experiments and Project on pages 17. 1.2.7 The information on each experiment should be given to the students before the

experiment is carried out so that they can plan their practical work.


2 RESTRICTED

1.2.8 The teacher should ensure that a student has been given a chance to acquire a particular skill before the assessment of that skill is made. For this purpose, the teacher should carry out similar experiments before carrying out the compulsory experiments.

1.2.9 The assessment of experimental skills should be done while the student is carrying out

the experiment and also on the student The assessment for the project should be done according to the project report and the oral presentation made by students.

1.2.10 For a student who is absent for an experiment with reason, the teacher can fix another

date for the students to carry out the experiment. 1.2.11 Students may write their practical work and project reports in either English or Bahasa

Melayu. The practical work reports is to be submitted to the teacher on the same day the experiment is carried out unless otherwise stated. (Refer to the Table of Summary of Experiments and project on pages 17) Practical work reports which are not submitted

1.2.12 Practical work reports which can be completed at home are to be submitted to the

teacher not later than 3 days from the date of the experiment. A penalty of 2 marks is to be imposed for the reports submitted late to the teacher. Practical work reports which are submitted later than 7 days from the date mark.

1.2.13 The teacher is required to set the dateline for the submission of project in the specified

date at the end of third term. A penalty of 2 marks is to be imposed for the reports submitted late to the teacher.

1.2.14 The oral presentation for the project work should be carried out by the teachers after the

assessment of the project report of all students. If the teacher suggests that changes are required towards the project report after the oral presentation, the student needs to correct the project report.

1.2.15 For a student who has transferred to another school, the previous school is to send the

student Form which is partially completed and signed by the subject teacher, to the student

1.2.16 All practical work and project reports, and Student's Record Form are evidence; and

should be kept by the school and destroyed under secure condition 6 months after the release of the STPM result in the following year.

1.3 Recording of Assessment Marks 1.3.1 Recording of the practical assessment marks of each student is to be done by the subject

teacher on Student's Record Form (See Appendix A on page 50). 1.3.2 For each student, the teacher is to record the date of the experiment, the experiment

number and mark given to each of the skills for the 13 compulsory experiments in the Student's Record Form. Marks are to be awarded in accordance with the practical work assessment guide on pages 4. The teacher will also record the date of oral presentation and mark given to each skill and component for the project in the Student's Record Form. Marks are to be awarded in accordance with the project assessment guide on pages 9.


3 RESTRICTED

1.3.3 Remarks on the following NotesStudent's Record Form of the student involved.

(a) An experiment carried out at a later date for a student who was absent for the experiment.

(b) Any penalty imposed due to late submission of practical and project reports to the teacher.

(c) A student who has not finished all the experiments allocated (reasons to be stated).

(d) A student who failed to submit all the practical and project reports (reasons to be stated).

1.3.4 Practical work and project assessment for the three terms should be completed four

weeks before the written examination for third term 1.3.5 Once the practical and project assessment for every term is completed, the marks for the

13 compulsory experiments and one project is to be calculated and written in the Form. The full total mark for this

practical work and project assessment is 225. 1.3.6 The total mark for each student must be submitted to MEC via electronic submission in

the specified date. 1.3.7 The teacher carrying out the practical and project assessment are required to make a

declaration that the entries of marks and the overall total mark in the Student's Record are correct by signing in the spaces provided.

1.4 Moderation 1.4.1 A common assessment standard for marking must be agreed upon if more than one

teacher in the same school is involved in assessing the student's practical work and project to ensure that the internal assessment is carried out fairly and effectively.

1.4.2 All component of assessment are subjected to moderation by the moderator appointed

by MEC.


4 RESTRICTED

1.5 Practical Work Assessment Guide 1.5.1 The practical work should be graded based on the assessment criteria below.

Skill Criterion Description Mark Range

Max Mark

A: Ability to use correct techniques and handling of apparatus and materials.

The assessment is made through unobtrusive observations of any two experiments for every term which involved the use of different apparatus. Students should not be aware of the assessment.

The student exhibits correct techniques in handling apparatus and materials. The experiment is conducted without guidance.

6

6 The student is sufficiently capable of using and handling apparatus with minimum guidance.

4

The student can carry out simple practical work using common apparatus and materials provided with guidance.

2

B: Observations, measurements and recording

The assessment is based on the practical reports for five experiments (first term and second term) while three experiments (third term); which require students to make, record and report observations or results. Teachers are required to carry out the same experiments for moderation purposes.

For Volumetric Analysis (a) Correct readings

(CR) and sufficient readings (SR)

Correct readings both the initial and final readings are recorded in the correct spaces and to two decimal places, except for zero.

Sufficient readings at least two

volume readings within the range of 0.10 cm3

1

1

5

(b) Correct average set (AS) and mean (M)

Correct average set correct difference

between the final and initial readings.

Correct mean arithmetic mean for titres used/obtained to two decimals places.

1

1


5 RESTRICTED


Max Mark

(c) Accuracy (The difference in mean value between the teacher and the student)

If the difference is between 0.00 cm3 and 0.30 cm3

1

For Physical Quantity and Technique (a) The table is

complete and the data are filled in the correct spaces.

(Minus ONE mark if the table is not complete)

2

(b) All calculations of the data in the table are correct.

1

(c) Appropriate decimal places.

Example: Temperature

readings up to one decimal place. (± 0.1 °C)

Weight measurements up to two decimal places (± 0.01 g)

Burette readings up to two decimal places (± 0.05 cm3)

1

(d) Accuracy (The difference in mean value between the teacher and the student)

If the difference between 0% to 10%

1


6 RESTRICTED


Max Mark

For Technique (Qualitative Analysis) (a) Filling the

column correctly (Minus ONE mark

if the table is not complete)

5

C: Interpretation of experimental observations and data

The assessment is based on the practical reports for four experiments in first term, four experiments in second term, and three experiments in third term whereby students are required to answer the stipulated questions, interpret data and draw deductions.

For Volumetric Analysis, and Physical Quantities and Technique (Synthesis) (a) Each question, other

than graphs which is correctly answered.

(Minus ONE mark for the incorrect answer)

(b) Experiment which involve graphs.

Axes labelled and correct units

(c) Correct shape of the graph

Max 4

1

1

6

For Technique (Qualitative Analysis) (a) Filling the

correctly. (Minus ONE mark

for each incorrect deduction)

(b) Deducing the identity of the salt/ion correctly

5

1


7 RESTRICTED


Max Mark

D: Design and Planning of Investigation

The assessment is based on the practical report for two experiments whereby the students are required to plan the experiment by themselves. Read the tabulation on page 16.

The practical report for first term should have the following format: (a) Title (b) Purpose (c) Materials and

apparatus (d) Theory/Introduction (e) Procedure (f) Results (Including

calculations)/ observation

(g) Conclusion (h) Comments (on the

experiments and/or results and/or safety measures/ precautions)

1

1

1

1

1

2

1

1

9

The practical report for second term and third term (except project report) should have the following format: (a) Title (b) Purpose (c) Materials and

apparatus (d) Theory/Introduction (e) Procedure/Tests (f) Observations (g) Deduction (h) Conclusion/Identity

of substance

4

4 1


8 RESTRICTED


Max Mark

E: Scientific ethics and values

Assessment is conducted throughout the terms in first term and second term by observations. The students are expected to exhibit the scientific ethics and values such as: self-reliance, trustworthiness, fairness, curiosity, inquisitiveness, initiative, innovative, receptive to new ideas, cooperative and caring for the environment.

(a) Excellent (b) Good (c) Moderate (d) Fair (e) Poor

5 4 3 2 1

5


9 RESTRICTED

1.6 Project Assessment Guide 1.6.1 The school will be notified of the theme of the project for the current year by MEC. The

students are free to propose the title of the project based on the theme given. 1.6.2 The groups are expected to complete the task at the end of third term of form six where

they will define the project focus, analyse and evaluate the information gathered, prepare an oral presentation and submit a written report.

1.6.3 The students will be assessed on their performances both as members of the group and

as individuals. 1.6.4 The performance of individual students and that of groups is assessed through the

following means: written report, overall quality of project report and oral presentation. 1.6.5 The report on project which has been done on third term should have the following

format: (a) Title (b) Abstract (c) Introduction (d) Methodology (e) Observations, result and discussion (f) Conclusion (g) References/Bibliography 1.6.6 The assessment framework of the project work is shown in the table below.

Component Group Individual Total Project report 66.67 % 66.67%

Project file 10% 10%

Oral Presentation 13.33% 10% 23.33%

Total 100% 1.6.7 The project report should be at least 800 words and not more than 1500 words. The

project report will be the assessment criteria.

1.6.8 The oral presentation will be assessed individually and as a group. On the individual

level, each student is given a minimum of 5 minutes per student. For groups of three students, a maximum time limit of 20 minutes is allocated; whereas for groups of two students, the maximum limit is 15 minutes. The group presentation also includes those that do not exceed 5 minutes. Each presentation will have a Q & A session.

1.6.9 Students need to be aware that the written work they submit must be entirely their own and cite any source that had been referred to. Teachers should try to encourage students to take responsibility for their learning, so that they accept ownership of the work and take pride in it.


10 RESTRICTED

1.6.10 The project report should be assessed based on the assessment criteria below.


Max Mark

B: Observations, measurements and recording

Title Clearly stated and related to the theme. 1 1

Abstract Clearly stated about the summary of the project.

1 1

Introduction includes: Theory and

Literature review

Presents some background information

with reference quoted

without reference quoted but have some information background

weak background of research

2 1 0

4

Problem statements

Presents relevant problem statements 0 1

Objective Presents relevant objectives of research 0 1

Methodology Data collection procedures and techniques planned and outlined clearly. Presents easy-to-follow steps which are logical, adequately detailed, and repeatable.

3 4

4

Most of the data collection procedures and techniques are understandable but some lack detail or are confusing.

1 2


11 RESTRICTED


Max Mark

C: Interpretation of experimental observations and data

Observation, result and discussion

Observation: Data is well organised in a data table or paragraph well written in complete sentences. Result: All calculations were completed, and a correct graph is drawn. Discussion: Presents a logical and well structured explanation for findings.

5 6

6

Observation: Data is organised in a data table or paragraph written in complete sentences. Result: All calculations were completed, but not correctly or a graph is drawn, but it is not the correct. Discussion: Presents a logical explanation for findings.

3 4

Observation: Data is not organised in a data table or paragraph not written in complete sentences. Result: All calculations were not completed and a graph was not complete. Discussion: Presents an illogical explanation for findings.

1 2


12 RESTRICTED


Max Mark

D: Design and Planning of Investigation

Conclusion Suggests specific changes that would improve the investigation. Recommends relevant action or research in the future findings.

1 1

References/ Bibliography

Correct writing of references and cited appropriately.

1 1

Presentation of the project report

Presentation of the project is excellent (well structured, clear, concise and precise).

2

2

Presentation of the projects is adequate. 1

Project file evidence

Evidences including log book are neat, accurate and clearly related to the project work and keep in a portfolio

3

3

Evidences including log book are neat and accurate related to the project work and keep in a portfolio

2

Not all important evidences including log book are neither neat nor accurate related to the project work and keep in a portfolio

1


13 RESTRICTED

The oral presentation should be assessed based on the assessment criteria below.


Max Mark

F: Oral Presentation

ICT (Group assessment)

Students have positive and appropriate experiences in a wide range of ICT applications.

2

2

Students experience a limited range of ICT applications.

1

Presentation (Group assessment)

Holds attention of entire audience with the use of direct eye contact, seldom looking at notes.

Speaker used techniques such as visual aids and props, anecdote, humour, surprising facts, direct audience participation.

The composition of the presentation elements exhibits creativity in effective delivery of the message.

2

2

Some eye contact was made, as entire report is read from notes.

Technique used to engage audience were minimal, or mainly ineffective.

The composition of the presentation elements exhibits limited creativity.

1


14 RESTRICTED


Max Mark

Communications (Individual assessment)

Presenter spoke clearly and at a good pace to ensure audience comprehension. Delivery was fluent and expressive.

Question answered with little difficulty. Very good knowledge of the project was demonstrated.

The presentation content was grammatically correct. Pronunciation and intonation is correct and confident.

3

3

Presenter usually spoke clearly to ensure audience comprehension. Delivery was usually fluent.

Most questions answered. Answers showed good knowledge and understanding of the project.

The presentation content was usually grammatically correct. Pronunciation and intonation is usually correct.

2


15 RESTRICTED


Max Mark

Presenter occasionally spoke clearly and at a good pace.

Not all questions could be answered. Questions answered with difficulty, and little knowledge of the project was demonstrated.

The presentation content was occasionally grammatically correct.

Pronunciation occasionally correct, but often hesitant and inaccurate.

1

STPM CHEMISTRY

16

1.7 Summary of the Allocation of Mark for Experiments and Project

Experiment Skill A Skill B Skill C Skill D Skill E Skill F First term

1

Any 2 experiment ! 6 marks

5 marks 9 marks

5 marks for overall assessment per term

2 5 marks 6 marks

3 5 marks 6 marks

4 5 marks 6 marks

5 5 marks 6 marks

Second term 6


5 marks 6 marks

5 marks for overall assessment per term

7 5 marks 6 marks

8 5 marks 6 marks

9 5 marks 9 marks

10 5 marks 6 marks

Third term 11


5 marks 6 marks

12 5 marks 6 marks

13 5 marks 6 marks

Project 10 marks 6 marks 7 marks 7 marks Total mark 36 marks 75 marks 66 marks 31 marks 10 marks 7 marks

Overall total mark 225 marks

STPM CHEMISTRY

17

1.8 Table of Summary of Experiments and Project

Experiment Topic Subtopic Purpose Mode of working

Report to be

completed

First Term

1 Volumetric analysis

Stoichiometry To determine the exact concentration of a monobasic acid, HX

Individually In the laboratory

2 Acid base and redox

To determine the mass of sodium ethanedioate used to prepare a solution containing sodium ethanedioate and hydrated ethanedioic acid


3 Purity and stoichiometry

To determine the purity of a sample of sodium sulphite


4 Physical Quantity

Reaction kinetics To determine the effect of temperature on the reaction rate


5 Equilibrium and solubility

To determine the solubility product, Ksp, of MX2 and enthalpy change of solution, solH


Second Term

6 Physical Quantity

Thermochemistry To determine the heat of reaction


7 Electrochemistry- Faraday's Laws

To determine the percentage purity of copper metal by electrolysis



18 RESTRICTED


Report to be

completed

8 Technique Qualitative analysis

To determine the cations and anions of inorganic substances


9 Qualitative analysis

To determine the cations and anions in inorganic salts


10 Technique-Synthesis

To determine the percentage of aluminium in a sample X by means of the preparation of a complex compound of aluminium with 8-hydroxyquinoline

Individually/Group

In the laboratory

Third Term


To study the reactions of alcohols and carbonyl compounds



To study the reactions of organic nitrogen compounds (amides, amines and their salts, amino acids and proteins)



To prepare a sample of 2-(4-hydroxyphenylazo) benzoic acid

Group At home

Project Volumetric analysis/ Physical quantity/

Technique

To enable students to acquire knowledge and skills in chemistry using ICT as well as to develop soft-skills

Group At the end of third term


19 RESTRICTED

1.9 Preparation of Solutions

For a 0.05 mol dm-3 solution of sodium ethanedioate, Na2C2O4, with a relative formula mass of 134.0, its concentration in g dm-3 can be prepared using the following equation.

Concentration in g dm 3 = molarity relative formula mass = 0.05 134 = 6.7

Standard solutions of sulphuric acid, glacial ethanoic acid, and ammonia are prepared as follows:

Step 1

By using the formula: Density = volumemass and the specifications given in the table below,

the volumes of reagents required for dilution can be calculated.

Acid Relative Molecular Mass Density or Specific Gravity Purity HCl H2SO4

HNO3

H2O2

NH3

CH3COOH

36.5 98.0 63.0 34.0 17.0 60.0

1.18 1.84 1.42 1.13

0.88 0.91 1.05

36% 98% 70% 35% 25%

99.5% Example: To prepare 1 dm3 of 0.1 mol dm 3 solution of HCl, the volume of concentrated acid

required = 36

1001.183.65

= 8.59 cm3.

Acid 0.10 mol dm 3 Volume required/cm3

HCl H2SO4

HNO3

H2O2

NH3

CH3COOH

3.65 9.80 6.30 3.40 1.70 6.00

8.6 5.4 6.3 8.6 7.7 5.7


20 RESTRICTED

Step 2 For more accurate work, these solutions need to be standardised using a standard solution of

sodium carbonate, Na2CO3. A standard solution of sodium carbonate can be prepared in the following way:

A little anhydrous sodium carbonate is dried in an evaporating dish to eliminate all traces of moisture. The substance is then cooled in a desiccator. The amount required (5.3 g dm 3 for a 0.05 mol dm 3 solution) is then weighed, dissolved and made into a solution in a standard flask. Acid solutions are then standardised using this solution.

Other concentrations of acid solutions can be prepared by diluting certain volumes of the acids and standardising them with the standard solution of sodium carbonate.

1.9.1 Standard solution of sodium thiosulphate Standard solutions of sodium thiosulphate, Na2S2O3.5H2O, (relative molecular mass

248.0) cannot be prepared directly because of its salt's nature of absorbing water. For accurate work, a solution which is prepared directly will not give good results, e.g. problems which involve the determination of relative molecular mass or relative atomic mass. Prepared solutions of thiosulphate are normally standardised with potassium iodate, which will react with iodide in acid solution to liberate iodine. Potassium iodate is used because this compound is available in a pure state.

1.9.2 Standard solution of Fe2+ ions To prepare this solution, use FeSO4.(NH4)2SO4.6H2O (relative molecular mass 392.0),

not FeSO4.7H2O. Iron(II) sulphate is easily oxidised by air. In the preparation of this solution, the double salt FeSO4.(NH4)2SO4.6H2O needs to be dissolved in dilute sulphuric acid and made up to the required volume with distilled or deionised water.

1.9.3 Iodine solution Dissolve 20.0 g of iodate-free potassium iodide in 30 40 cm3 distilled water. Weigh

about 12.7 g iodine and transfer it to the 1 dm3 volumetric flask containing concentrated potassium iodide solution. Shake the mixture until all the iodine has dissolved. Make up the solution to the mark with distilled water.

1.9.4 Hydrogen peroxide solution

The strength of a solution of hydrogen peroxide is usually mentioned in volumes , e.g: 20 - volume hydrogen peroxide, 100 - volume hydrogen peroxide, etc. For a 20

- volume solution, 1 cm3 of hydrogen peroxide will decompose to yield 20 cm3 of oxygen at s.t.p.

2H2O2 2H2O + O2

68 g of hydrogen peroxide liberates 22.4 litres of oxygen at s.t.p.

1 g of hydrogen peroxide liberates 68

422. litres of oxygen at s.t.p.

1 litre of 20-volume hydrogen peroxide liberates 20 litres of oxygen at s.t.p.

1 litre of 20-volume hydrogen peroxide contains 64.22

20= 60.8 g.


21 RESTRICTED

Therefore, to prepare a 0.1 mol dm-3 solution of H2O2, about 5.6 cm3 of 20 - volume hydrogen peroxide must be diluted to make 1 litre. Other concentrations can be prepared by diluting suitable volumes of 20 - volume H2O2. Hydrogen peroxide solutions cannot be kept for long periods of time because of their strong tendency to decompose. Hence, hydrogen peroxide solutions for volumetric work must be standardised with a standard solution of potassium manganate(VII) before use.

1.9.5 Iodine - potassium iodide solution (Iodoform Test) Iodine dissolves sparingly in water. Its solution is prepared by adding 20.0 g potassium

iodide and 10.0 g iodine in 80 cm3 distilled water. The mixture is stirred to form a deep brown solution.

1.9.6 Fehling's solution can be prepared as follows:

(a) Dissolve 17.32 g copper(II) sulphate pentahydrate in 200 cm3 of distilled water and dilute the solution to 250 cm3.

(b) Dissolve 86.5 g of sodium potassium tartarate and 35 g sodium hydroxide in

100 cm3 of distilled water and dilute the solution to 250 cm3.

To prepare the Fehlings solution, mix 2.5 cm3 3

immediately before use. 1.9.7 Tollen's reagent Add a drop of 2.5 mol dm 3 of sodium hydroxide solution to a 2 cm3 of 0.3 mol dm 3 of

aqueous silver nitrate in a test tube. Add 3.0 mol dm 3 of ammonia drop by drop until all the precipitate (silver oxide) dissolves.

1.9.8 2,4-Dinitrophenylhy agent) Dissolving 3 g of 2,4-dinitrophenylhydrazine in 15 cm3 concentrated sulphuric acid.

This solution is added with stirring to 20 cm3 of distilled water and 70 cm3 of 95% ethanol and filtered.

1.9.9 Indicator solutions

(a) Methyl orange Dissolve 1 g of the solid in 1 dm3 of water.

(b) Screened methyl orange Dissolve 1 g of methyl orange and 1.5 g of p-xylene cyanol in 500 cm3 of

alcohol and dilute the solution to 1 dm3 with water.

(c) Phenolphthalein Dissolve 1 g of the solid in 500 cm3 of alcohol and dilute the solution to 1 dm3

with water.

(d) Starch indicator (usually 1%) Make a paste of 1 g of starch with cold water, then pour boiling water and make up to 100 cm3.


22 RESTRICTED

1.10 Guidelines for Experiments Experiment 1 Notes for Teachers This experiment is to be conducted after the teacher has taught:

(a) Preparation of standard solutions

(b) Skills involving acid-base titration Materials A suitable monobasic acid is hydrochloric or ethanoic acid, about 150 cm3 per student.

A suitable base is sodium hydroxide or sodium carbonate with suitable mass as required by the student.

A suitable indicator is phenolphthalein or methyl orange.

Distilled water, about 250 cm3 per student. Apparatus per student 250 cm3 volumetric flask and stopper

Electric balance 0.01 g or equivalent (common use)

One 25 cm3 pipette and pipette filler

One 100 cm3 volumetric flask and stopper

Two 50 cm3 burettes

One retort stand and clamp

One white tile

One wash bottle filled with distilled water

Spatula

Three titration flasks

Other suitable fittings and apparatus Skills A, B, D, and E Examples of skills A that can be seen are as follows:

(a) Reasonable quantities of substance used

(b) Method of weighing to obtain an exact weight of substances

(c) Technique of setting up, rinsing and filling up of the burette

(d) Technique of rinsing, filling up and transferring the solution from the pipette into the titration flask

(e) Addition of indicator at the appropriate time

(f) Method of holding and shaking the titration flask during the titration process

(g) Method of washing off the solution from the sides of the titration flask with distilled water before reaching the end-point


23 RESTRICTED

Experiment 2 Notes for Teachers Materials KA 1 is a solution containing 3.00 g of sodium ethanedioate, Na2C2O4, and 4.00 g

hydrated ethanedioic acid, H2C2O4.2H2O, per dm3, about 250 cm3 per student.

KA 2 is a solution containing 3.50 g potassium manganate(VII), KMnO4, per dm3, about 120 cm3 per student.

KA 3 is a solution containing 4.00 g sodium hydroxide per dm3, about 120 cm3 per student.

KA 4 is 1.00 mol dm-3 sulphuric acid, about 120 cm3 per student.

Phenolphthalein as an indicator. Apparatus per student Two 25 cm3 pipettes and pipette fillers

Two 50 cm3 burettes

Six titration flasks

Two retort stands and clamps

One 50 cm3 measuring cylinder

Two white tiles


One thermometer 0 C 100 C (± 1.0 C) Skills A, B, C and E Examples of skills A that can be seen are as follows:

(a) Technique of setting up, rinsing and filling up of the burette

(b) Technique of rinsing, filling up and transferring the solution from the pipette into the titration flask

(c) Addition of indicator at the appropriate time

(d) Method of holding and shaking the titration flask during the titration process

(e) Method of washing off the solution from the sides of the titration flask with distilled water before reaching the end-point

(f) Technique of using measuring cylinder to measure volume of solution

(g) Technique of heating the solution before titration


24 RESTRICTED

Experiment 3 Notes for Teachers Materials KA 1 is a 0.025 mol dm 3 iodine solution prepared by dissolving 6.35 g of iodine in 10%

solution of potassium iodide per dm3, about 250 cm3 per student.

KA 2 is a solution containing 12.41 g of sodium thiosulphate per dm3, about 200 cm3 per student.

KA 3 is a solution containing 3.15 g of anhydrous sodium sulphite, Na2SO3, per dm3, about 150 cm3 per student.

KA 4 is 2 g sodium hydrogencarbonate, about 8 g per student.

Starch as an indicator. Apparatus per student One 25 cm3 pipette and pipette filler

One 50 cm3 pipette

Three titration flasks

One 50 cm3 burette


One white tile

One wash bottle filled with distilled water Skills A, B, C, and E Examples of skills A that can be seen are as follows:

(a) Technique of setting up, rinsing and filling up of the burette

(b) Technique of rinsing, filling up and transferring the solution from the pipette into the titration flask

(c) Addition of indicator at the appropriate time

(d) Method of holding and shaking the titration flask during the titration process

(e) Method of washing off the solution from the sides of the titration flask with distilled water before reaching the end-point


25 RESTRICTED

Experiment 4 Notes for Teachers Materials KA 1 is a solution containing 24.90 g of potassium iodide per dm3, about 150 cm3 per

student.

KA 2 is a 0.5% starch solution, about 50 cm3 per student.

KA 3 is a solution containing 12.41 g of sodium thiosulphate per dm3, about 50 cm3 per student.

KA 4 is a solution containing 8.60 cm3 of hydrogen peroxide (35%) per dm3, about 300 cm3 per student.

KA 5 is a solution containing 54.0 cm3 of concentrated sulphuric acid per dm3, about 150 cm3 per student.

Ice and hot water are used as water bath and also to obtain different temperatures.

Distilled water, about 150 cm3 per student. Apparatus per student One 25 cm3 pipette and pipette filler



One 50 cm3 burette


One conical flask

One stopwatch

One 150 cm3 beaker

One thermometer 0 C 100 C ( 1.0 C)


One white tile Skills A, B, C, and E Examples of skills A that can be seen are as follows:

(a) Technique of obtaining and maintaining the required temperatures

(b) Accuracy in noting the time when the blue colour appears Examples of skills B and C that can be seen are as follows:

(a) Recording time and temperature in the correct spaces

(b) Plotting of graph from the information obtained

(c) Interpretation of the graph plotted


26 RESTRICTED

Experiment 5 Notes for Teachers Materials KA 1 is solution containing 33.10 g of lead(II) nitrate per dm3, about 150 cm3 per student.

KA 2 is solution containing 29.25 g of sodium chloride per dm3, about 100 cm3 per student.

Apparatus per student Two burettes

Five boiling tubes

One thermometer 0 ºC 100 ºC (± 1.0 ºC)

Two 250 cm3 beakers

Two retort stands and clamps

One test-tube holder

One water bath Skills A, B, C and E Examples of skills B and C that can be seen are as follows:

(a) Recording of volume and temperature in the correct spaces

(b) Plotting of graph from the information obtained

(c) Interpretation of the graph obtained


27 RESTRICTED

Experiment 6 Notes for Teachers Materials KA 1 is a solution containing 172 cm3 of concentrated hydrochloric acid per dm3, about

100 cm3 per student.

KA 2 is 2.00 g to 2.40 g of solid anhydrous sodium carbonate in a stoppered test-tube; one test-tube of KA 2 per student.

KA 3 is 2.70 g to 3.10 g of sodium hydrogencarbonate in a stoppered test-tube; one test-tube of KA 3 per student.

Apparatus per student One 50 cm3 burette


One plastic/polystyrene cup

One thermometer 0 C 110 C ( 0.2 C)

One wash bottle filled with distilled water Electric balance 0.01 g (common use) Skills A, B, C, and E Examples of skills B that can be seen are as follows:

(a) Measurement of the initial temperature is only carried out when the temperature is stable

(b) Correct method of weighing to obtain an exact weight of KA 2

(c) Weights to be recorded to the nearest 0.01 g in the correct spaces

(d) Temperatures to be recorded to the nearest 0.2 C in the correct spaces


28 RESTRICTED

Experiment 7 Notes for Teachers Materials Solution containing 250 g of CuSO4.5H2O per dm3, about 300 cm3 per student.

Propanone, about 100 cm3 per student.

Distilled water, about 200 cm3 per student. Apparatus per student One 100 cm3 measuring cylinder

One 250 cm3 beaker

Two pieces of copper plates measuring 5 cm 4 cm 0.2 cm

Five connecting wires with crocodile clips

One ammeter, 0 A 3 A

One rheostat, 11

One switch

Four dry cells or source of direct current 6 V

One stopwatch

Hair dryer (common use)

Electric balance 0.01 g (common use)


Other suitable fittings and apparatus Skills A, B, D and E Examples of skill D that can be seen are as follows:

(a) Neat and proper planning in following common procedures

(b) Selecting, setting up of apparatus, and using of materials correctly and completely

(c) Obtaining and recording of the masses of both the copper plates at the anode and the cathode before and after the electrolysis process

(d) Time planning to be compatible with the experiment


29 RESTRICTED

Experiment 8 Notes for Teachers (a) The teacher has to supply different salts to each of the classes taught.

(b) The teacher has to supply a different salt each year to the students. Materials KA 1, solid MgS2O3 or MgSO3 or CuSO3 or Pb(CH3COO)2 or Ca(CH3COO)2

KA 2, a mixture of solids Al2(SO4)3 and (NH4)2SO4 or a mixture of solids Zn(NO3)2 and NH4NO3

Common acids (concentrated and dilute)

Common alkalis (concentrated and dilute)

Aqueous solution of iron(III) chloride, approximately 50 g dm 3

Dissolve 135 g of solid iron(III) chloride in distilled water containing 20 cm3 of concentrated hydrochloric acid and make up the volume of solution to 1 dm3.

Aqueous solution of ammonium chloride, approximately 50 g dm 3

Aqueous solution of silver nitrate, approximately 50 g dm 3

Aqueous solution of disodium hydrogen phosphate, approximately 50 g dm 3

Aqueous solution of potassium chromate(VI), approximately 50 g dm 3

Aqueous solution of potassium iodide, approximately 50 g dm 3

Aqueous solution of sodium ethanoate, approximately 50 g dm 3

Aqueous solution of sodium carbonate, approximately 50 g dm 3 Apparatus per student One test-tube rack with six test tubes

One hard glass test-tube with delivery tube


One spatula

One filter funnel and two pieces of filter paper

One teat pipette

One Bunsen burner Red and blue litmus papers

Wooden splint

One wash bottle filled with distilled water Skills A, B, C, and E Examples of skills B and C that can be seen are as follows:

(a) Correct observations for each of the tests done

(b) Correct deductions which are consistent with correct observations


30 RESTRICTED

Experiment 9 Notes for Teachers (a) The teacher has to supply different salts and other suitable reagents to each of the classes

taught. (b) The teacher has to supply different salts and other suitable reagents each year to the

students. Materials KA 1, a mixture of solids KI and KNO3 or a mixture of solids KBr and KNO3

Common acids (concentrated and dilute)

Common alkalis (concentrated and dilute)

Aqueous solution of silver nitrate, approximately 50 g dm 3

Aqueous solution of iron(II) sulphate, approximately 50 g dm 3

Aqueous solution of lead(II) ethanoate , approximately 50 g dm 3

Aqueous solution of ammonium chloride, approximately 50 g dm 3

1,1,1-trichloroethane (test for halogens)

Other suitable reagents Apparatus per student One test-tube rack and six test-tubes

One hard glass test-tube and delivery tube


One spatula

One filter funnel and two pieces of filter paper

One teat pipette

One Bunsen burner Red and blue litmus papers

Wooden splint

One wash bottle filled with distilled water Skills A, B, D, and E Examples of skill B that can be seen are as follows:

Tests on KA (a) Correct observations for each of the tests done

(b) Correct deductions which are consistent with correct observations


31 RESTRICTED

Experiment 10 Notes for Teachers (a) The students are required to submit the product of the experiment together with their

reports. Materials KA 1 is a solution of 8-hydroxyquinoline prepared by dissolving 2.00 g of

8-hydroxyquinoline in 100 cm3 of 2 mol dm 3 ethanoic acid, about 50 cm3 per student.

KA 2 is a solution containing 154.00 g of CH3COONH4 per dm3, about 100 cm3 per student.

KA 3 is a potassium alum, KAl(SO4)2 .12H2O, about 0.25 g to 0.30 g per student.

KA 4 is a solution containing 170 cm3 of concentrated hydrochloric acid per dm3, about 10 cm3 per student.

Distilled water, about 200 cm3 per student.

Ice cubes which are used as water bath. Apparatus per student Electric balance 0.01 g (common use)

One 250 cm3 beaker

One Bunsen burner

One tripod stand and wire gauze

One thermometer 0 C to 100 C

One crucible and lid

One filter funnel and filter paper

One teat pipette

One 250 cm3 conical flask


Oven (common use)

Magnetic stirrer, one per four students

One 50 cm3 measuring cylinder Skills A, B, C, and E Examples of skill A that can be seen are as follows:

(a) Correct technique of weighing

(b) Ensuring that all product are removed from the filter paper

(c) Ensuring that the temperature of the oven is 120 C


32 RESTRICTED

Experiment 11 Notes for Teachers (a) The iodine potassium solution, Tollen's reagent and Brady's reagent should be freshly

prepared before the experiment begins. Fehlings' solution A and Fehlings' solution B should be mix immediately before use with the unknown.

Materials KA 1, absolute ethanol, about 10 cm3 per student KA 2, propanal or acetone, about 10 cm3 per student

Concentrated and 1 mol dm 3 sulphuric acid

Glacial ethanoic acid

1 mol dm-3 sodium hydroxide solution

Acidified of potassium manganate(VII) solution, approximately 3 g dm 3

Iodine-potassium iodide solution (Iodoform Test) F

2,4 Apparatus per student

One test-tube rack and six test-tubes

One test tube holder

One Bunsen burner

One 250 cm3 beaker


One teat pipette /dropper Skills A, B, C and E Examples of skills B and C that can be seen are as follows:


(b) Correct observations for each of the tests done

(c) Correct deductions which are consistent with the observations


33 RESTRICTED

Experiment 12 Notes for Teachers (a) KA 2 is smelly, with an unpleasant odour and should be administered in a fume chamber. Materials KA 1, 2.0 g ethanamide KA 2, 5 cm3 of 1-butanamine Common acids (concentrated and dilute) Common alkalis (concentrated and dilute) Bromine water Dissolve bromine liquid in water to make a saturated solution Sodium nitrite

5% Sodium hydrogencarbonate solution

Propanone

Ice cubes

Universal indicator Apparatus per student One test-tube rack and six test-tubes

One hard glass test tube and delivery tube


One spatula

One teat pipette

One Bunsen burner

Blue and red litmus paper

Wooden splinter


One 250 cm3 beaker Skills A, B, C and E Examples of skill A that can be seen are as follows:

(a) Reagents to be added slowly so that all the stages of observation can be recorded Examples of skills B and C that can be seen are as follows:


(b) Correct deductions which are consistent with the observations


34 RESTRICTED

Experiment 13 Notes for Teachers (a) The students are required to submit the product of the experiment together with their

reports.

(b) Since phenol is a highly hygroscopic substance (absorbing water from the air), the stock alkaline solution of phenol must be prepared immediately after the bottle containing phenol is open and the solution is kept in the big amber glass bottles.

(c) Common salt may be added to the ice to lower the temperature of ice water bath to 5 °C. Materials KA 1 is solid 2-aminobenzoic acid, about 3.4 g per group.

KA 2 is a solution containing 140.0 cm3 of concentrated hydrochloric acid (37 wt.%) per dm3, about 65 cm3 per group.

KA 3 is solid sodium nitrite, about 1.9 g per group.

KA 4 is solution prepared by dissolving 54 g of sodium hydroxide in about 900 cm3 of distilled water followed by dissolving 28.24 g of phenol, then water is added to a 1 dm3 mark; about 85 cm3 per group. If phenol in a liquid form, it is estimated that there is 8 g phenol in 100 cm3 in the liquid solution. To prepare the KA4 solution, we need to dissolve 54 g of sodium hydroxide in about 900 cm3 of distilled water followed by dissolving 353 cm3 of phenol, then water is added to a 1 dm3 mark; about 85 cm3 per group.

KA 5 is a solution containing 330.0 cm3 of concentrated hydrochloric acid (37 wt.%) per dm3, about 35 cm3 per group.

Distilled water, about 250 cm3 per group.

Acetone, about 70 cm3 per group.

Sodium chloride (common salt)

Ice cubes which are used as water bath. Apparatus per group Electric balance ± 0.01 g (common use) One 125 cm3 conical flask Two 100 cm3 graduated cylinders One 100 cm3 beaker One PVC basin One teat pipette One teat pipette rubber bulb One thermometer 0 to 100 C One glass, spoon-paddle ends spatula, about 30 cm long One wash bottle filled with distilled water One Buchner filter funnel, its conical flask and filter paper A watch glass/evaporating dish


35 RESTRICTED

Skills A, B, C and E Examples of skill A that can be observed are as follows:

(a) Correct method employed in weighing

(b) Correct method employed in handling the Buchner filtration apparatus

(c) Correct technique employed in carrying out the crystallization and drying of crystals


36 RESTRICTED

1.11 List of Apparatus and Materials 1.11.1 List of Apparatus and Materials by Experiments

Experiment no. (Mode of working) Apparatus/Materials Quantity used

1 (Individual)

250 cm3 volumetric flask and stopper Electric balance 0.01 g common use 25 cm3 pipette and pipette filler 1 100 cm3 flask and stopper 1 50 cm3 burette 2 Retort stand and clamp 1 White tile 1 Wash bottle filled with distilled water 1 Titration flask 3 150 cm3 hydrochloric or ethanoic acid Sodium hydroxide or sodium carbonate Phenolphthalein or methyl orange 250 cm3 distilled water

2 (Individual)

25 cm3 pipette and pipette filler 2 50 cm3 burette 2 Titration flask 6 Retort stand and clamp 2 50 cm3 measuring cylinder 1 White tile 2 Wash bottle filled with distilled water 1 Thermometer 0 C 100 C ( 1.0 C) 1 Sodium ethanedioate Hydrated ethanedioic acid Potassium manganate(VII) Sodium hydroxide Sulphuric acid Phenolphthalein

3 (Individual)

25 cm3 pipette and pipette filler 1 50 cm3 pipette 1 Titration flask 3 50 cm3 burette 1 Retort stand and clamp 1 White tile 1 Wash bottle filled with distilled water 1 Iodine solution Potassium iodide Sodium thiosulphate Anhydrous sodium sulphite Sodium hydrogencarbonate Starch


37 RESTRICTED


4 (Individual)

150 cm3 beaker 1 Wash bottle filled with distilled water 1 50 cm3 burette 1 Stopwatch 1 White tile 1 250 cm3 conical flask 1 Retort stand and clamp 1 25 cm3 pipette and pipette filler 1 10 cm3 measuring cylinder 1 50 cm3 measuring cylinder 1 Thermometer 0 C 100 C ( 1.0 C) 1 Distilled water, hot water, and ice Sulphuric acid Hydrogen peroxide Potassium iodide Sodium thiosulphate Starch

5 (Individual)

50 cm3 burette 2 Boiling tube 5 Thermometer 0 C 100 C ( 1.0 C) 1 Water bath 1 250 cm3 beaker 2 Retort stand and clamp 2 Test-tube holder 1 Lead(II) nitrate Sodium chloride

6 (Individual)

50 cm3 burette 1 Wash bottle filled with distilled water 1 Plastic/polystyrene cup 1 Electric balance ( 0.01 g) Common use Retort stand and clamp 1 Thermometer 0 C 110 C ( 0.2 C) 1 Hydrochloric acid Sodium hydrogen carbonate Anhydrous sodium carbonate


38 RESTRICTED


7 (Individual)

Ammeter 0 A 3 A ( 0.1 A) 1 250 cm3 beaker 1 Wash bottle filled with distilled water 1 Stopwatch 1 Copper plate measuring 5 cm 4 cm 0.2 cm 2 Hair dryer Common use Electric balance ( 0.01 g) Common use 11 rheostat 1 Dry cell (source of direct current 6 V) 4 Connecting wire with crocodile clips 5 100 cm3 measuring cylinder 1 Switch 1 Distilled water Copper(II) sulphate pentahydrate Propanone

8 (Individual)

Test-tube rack with six test tubes 1 Hard glass test-tube with delivery tube 1 Test-tube holder 1 Spatula 1 Filter funnel and two pieces of filter paper 1 Teat pipette 1 Bunsen burner 1 Red and blue litmus papers Wooden splint Wash bottle filled with distilled water 1 Magnesium thiosulphate(VI) or magnesium sulphite or copper sulphite or calcium ethanoate or lead(II) ethanoate

Aluminium sulphate or ammonium sulphate or zinc nitrate or ammonium nitrate

Nitric acid Ammonia Hydrochloric acid Sodium hydroxide Iron(III) chloride Ammonium chloride Silver nitrate Disodium hydrogen phosphate Potassium chromate(VI) Potassium iodide Sodium carbonate Sodium ethanoate


39 RESTRICTED


9 (Individual)

Test-tube rack and six test-tubes 1 Hard glass test-tube and delivery tube 1 Test-tube holder 1 Spatula 1 Filter funnel and two pieces of filter paper 1 Teat pipette 1 Bunsen burner 1 Red and blue litmus papers Wooden splint Wash bottle filled with distilled water 1 Hydrochloric acid Nitric acid Ammonia Sodium hydroxide

Silver nitrate Iron(II) sulphate Lead(II) ethanoate Ammonium chloride 1,1,1-trichloroethane Other reagents for testing iodine and nitrate ions Potassium iodide Potassium nitrate Copper(II) carbonate or magnesium carbonate or calcium carbonate or manganese carbonate or nickel(II) carbonate or barium chloride or magnesium chloride or calcium chloride

10 (Individual/

Group)

250 cm3 beaker 1 Wash bottle filled with distilled water 1 250 cm3 conical flask 1 Oven Common use Electric balance ( 0.01 g) Common use Magnetic stirrer 1 per 4 persons Teat pipette 1 Bunsen burner 1 Refrigerator Common use Filter funnel and filter paper 1 Crucible with lid 1 Tripod and wire gauze 1 50 cm3 measuring cylinder 1


40 RESTRICTED


Thermometer 0 C 100 C ( 1.0 oC) 1 Ethanoic acid Hydrochloric acid Ice Ammonium ethanoate 8-hydroxyquinoline Potassium alum, KAl(SO4)2.12H2O

11 (Individual)

Test-tube rack and six test tubes 1 Test-tube holder 1 Bunsen burner 1 250 cm3 beaker 1 Wash bottle filled with distilled water 1 Teat pipette/Dropper 1 Absolute ethanol Propanal Propanone Butanone or 1-butanol Sulphuric acid 99.5% ethanoic acid Sodium hydroxide Potassium manganate(VII) Potassium iodide Iodine Silver nitrate Ammonia Copper(II) sulphate pentahydrate Sodium potassium tartrate tetrahydrate 2,4-dinitrophenylhydrazine 95% ethanol


41 RESTRICTED


12 (Individual)

Test-tube rack and six test tubes 1 Hard glass test-tube and delivery tube 1 Test-tube holder 1 Spatula 1 Teat pipette 1 Bunsen burner 1 Red and blue litmus papers Wooden splinter Wash bottle filled with distilled water 1 250 cm3 beaker 1 Ethanamide 1-butanamine Sulphuric acid Hydrochloric acid Sodium hydroxide Bromine water Sodium nitrite Sodium hydrogencarbonate Propanone Ice Universal indicator

13 (Group)

Electric balance ( 0.01 g) common use 125 cm3 conical flask 1 100 cm3 graduated cylinder 2 100 cm3 beaker 1 PVC basin 1 Teat pipette 1 Teat pipette rubber bulb 1 Thermometer 0 C 100 C ( 0.01) 1 Glass, spoon-paddle ends spatula 1 Wash bottle filled with distilled water 1 Buchner filter funnel 1 Conical flask 1 Filter paper 1 Watch glass/evaporating dish 1 2-aminobenzoic acid Hydrochloric acid Sodium nitrite Sodium chloride Sodium hydroxide Phenol Ice


42 RESTRICTED

1.11.2 List of apparatus and materials by experiments

No Apparatus Quantity used

Experiment no.

Mode of working

1 Ammeter 0 A 3 A ( 0.1 A) 1 7 Ind 2 100 cm3 beaker 1 13 Group 3 150 cm3 beaker 1 4 Ind 4 250 cm3 beaker 1

2 1 1 1

7 5

10 11 12

Ind Ind

Ind/Group Ind Ind

5 Boiling tube 5 5 Ind 6 Buchner filter funnel 1 13 Group 7 Bunsen burner 1

1 1 1 1

8 9

10 11 12

Ind Ind

Ind/Group Ind Ind

8 50 cm3 burette 2 2 1 1 2 1

1 2 3 4 5 6

Ind Ind Ind Ind Ind Ind

9 Connecting wire with crocodile clip 5 7 Ind 10 125 cm3 conical flask 1 13 Group 11 250 cm3 conical flask 1

1 4

10 Ind

Ind/Group 12 100 cm3 flask and stopper 1 1 Ind 13 250 cm3 volumetric flask and stopper 1 Ind 14 Copper plate 5 cm 4 cm 0.2 cm 2 7 Ind 15 Crucible with lid 1 10 Ind/Group 16 10 cm3 measuring cylinder 1 4 Ind 17 50 cm3 measuring cylinder 1

1 1

2 4

10

Ind Ind

Ind/Group 18 100 cm3 measuring cylinder 1 7 Ind 19 100 cm3 graduated cylinder 2 13 Group 20 Dry cell 1.5 V (source of direct current

6 V) 4 7 Ind


43 RESTRICTED


Experiment no.

Mode of working

21 Electric balance ( 0.01 g) C C C C C

1 6 7

10 13

Ind Ind Ind

Ind/Group Group

22 Filter funnel 1 1 1

8 9

10

Ind Ind

Ind/Group 23 Filter paper 8

9 10 13

Ind Ind

Ind/Group Group

24 Glass, spoon-paddle ends spatula 1 13 Ind 25 Hair dryer C 7 Ind 26 Hard glass test-tube and delivery tube 1

1 1

8 9

12

Ind Ind Ind

27 Magnetic stirrer 1 10 Ind/Group 28 Oven C

C 10 13

Ind/Group Group

29 Pipette filler 1 2 1 1

1 2 3 4

Ind Ind Ind Ind

30 25 cm3 pipette 1 2 1 1

1 2 3 4

Ind Ind Ind Ind

31 50 cm3 pipette 1 3 Ind 32 Plastic/polystyrene cup 1 6 Ind 33 PVC basin 1 13 Group 34 Red and blue litmus papers 8

9 12

Ind Ind Ind

35 Refrigerator C 10 Ind/Group 36 Retort stand and clamp 1

2 1 1 2 1

1 2 3 4 5 6


37 11 rheostat 1 7 Ind


44 RESTRICTED


Experiment no.

Mode of working

38 Spatula 1 1 1

8 9

12

Ind Ind Ind

39 Stopwatch 1 1

4 7

Ind Ind

40 Switch 1 7 Ind 41 Teat pipette 1

1 1 1 1 1

8 9

10 11 12 13

Ind Ind

Ind/Group Ind Ind Ind

42 Teat pipette rubber bulb 1 13 Group 43 Test-tube holder 1

1 1 1

8 9

11 12

Ind Ind Ind Ind

44 Test-tube rack and six test-tubes 1 1 1 1

8 9

11 12

Ind Ind Ind Ind

45 Titration flask 3 6 3

1 2 3

Ind Ind Ind

46 Thermometer 0 oC ! 100 oC ( 1.0 oC) 1 1 1 1 1

2 4 5

10 13

Ind Ind Ind

Ind/Group Group

47 Thermometer 0 oC ! 110 oC ( 0.2 oC) 1 6 Ind 48 Tripod and wire gauze 1 10 Ind/Group 49 Wash bottle 1

1 1 1 1 1 1 1 1 1 1 1

1 2 3 4 6 7 8 9

10 11 12 13

Ind Ind Ind Ind Ind Ind Ind Ind

Ind/Group Ind Ind

Group


45 RESTRICTED


Experiment no.

Mode of working

50 Watch glass/evaporating dish 1 13 Ind 51 Water bath 1 5 Ind 52 White tile 1

2 1 1

1 2 3 4

Ind Ind Ind Ind

53 Wooden splint 1 1 1

8 9

12

Ind Ind Ind

! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


46 RESTRICTED

1.11.3 List of chemicals by experiments

No Chemical Quantity used

Experiment no.

Mode of working

1 Absolute ethanol 11 Ind 2 2-aminobenzoic acid 13 Group 3 Aluminium sulphate 8 Ind 4 Ammonia 8

9 11

Ind Ind Ind

5 Ammonium chloride 8 9

Ind Ind

6 Ammonium ethanoate, CH3COONH4 10 Ind/Group 7 Ammonium nitrate 8 Ind 8 Ammonium sulphate 8 Ind 9 Anhydrous sodium sulphite 3 Ind

10 Barium chloride 9 Ind 11 Bromine water 12 Ind 12 Butanamine 12 Ind 13 Butanone or 1-butanol 11 Ind 14 Calsium carbonate 9 Ind 15 Calsium chloride 9 Ind 16 Calsium ethanoate 8 Ind 17 Copper(II) carbonate 9 Ind 18 Copper(II) sulphate pentahydrate 7

11 Ind Ind

19 Copper sulphite 8 Ind 20 9 Ind 21 2,4-Dinitrophenylhydrazine 11 Ind 22 Disodium hydrogen phosphate 8 Ind 23 Ethanoic acid

1

10 Ind

Ind/Group 24 Ethanamide 12 Ind 25 99.5% Ethanoic acid 11 Ind 95% Ethanol 11 Ind

26 Hot water and ice 4 Ind 27 Hydrated ethanedioic acid 2 Ind 28 Hydrochloric acid 1

6 8 9

10 12 13

Ind Ind Ind Ind

Ind/Group Ind

Group


47 RESTRICTED


Experiment no.

Mode of working

29 Hydrogen peroxide 4 Ind 30 8-Hydroxyquinoline 10 Ind/Group 31 Ice 10

12 13

Ind/Group Ind

Group 32 Iodine 3

11 Ind Ind

33 Iron(II) sulphate 9 Ind 34 Iron(III) chloride 8 Ind 35 Lead(II) ethanoate 8

9 Ind Ind

36 Lead(II) nitrate 5 Ind 37 Manganese carbonate 9 Ind 38 Magnesium carbonate 9 Ind 39 Magnesium chloride 9 Ind 40 Magnesium sulphite 8 Ind 41 Magnesium tiosulphate(VI) 8 Ind 42 Methyl orange 1 Ind 43 Nickel(II) carbonate 9 Ind 44 Nitric acid 8

9 Ind Ind

45 Phenol 13 Group 46 Phenolphthalein 1

2 Ind Ind

47 Potassium alum, KAl(SO4)2.12H2O 10 Ind/Group 48 Potassium iodide 3

4 8 9

11

Ind Ind Ind Ind Ind

49 Potassium chromate(VI) 8 Ind 50 Potassium manganate(VII) 2

11 Ind Ind

51 Potassium nitrate 9 Ind 52 Propanal 11 Ind 53 Propanone 7

11 12

Ind Ind Ind

54 Silver nitrate 8 9

11

Ind Ind Ind


48 RESTRICTED


Experiment no.

Mode of working

55 Sodium ethanedioate 2 Ind 56 Sodium ethanoate 8 Ind 57 Sodium hydrogen carbonate 3

6 12

Ind Ind Ind

58 Sodium carbonate 1 6 8

Ind Ind Ind

59 Sodium hydroxide 1 2 8 9

11 12 13


Group 60 Sodium chloride 5 Ind 61 Sodium nitrite 12

13 Ind

Group 62 Sodium potassium tartrate tetrahydrate 11 Ind 63 Sodium tiosulphate 3

4 Ind Ind

64 Starch 3 4

Ind Ind

65 Sulphuric acid 2 4

11 12

Ind Ind Ind Ind

66 1,1,1-trichloroethane 9 Ind 67 Universal indicator 12 Ind 68 Zinc nitrate 8 Ind


49 RESTRICTED

Appendix A Form

SCHOOL-BASED ASSESSMENT OF PRACTICAL

CHEMISTRY (PAPER 962/4) STPM 2014

Name of school/institute Name of student Centre no./Index no. S / I/C no.

Skill Mark for skill assessed Notes A B C D E F

Study term Date Experiment mark mark mark mark mark mark mark mark mark mark

First

Exp 1 Exp 2 Exp 3 Exp 4 Exp 5

Second

Exp 6 Exp 7 Exp 8 Exp 9 Exp10

Third

Exp 11 Exp 12 Exp 13 Project

Total mark Overall total mark

I certify that the marks and details recorded above are true. I certify that the marks and details recorded above are true.

Name: Name: Date: Date: Contact number (H/P): Contact number (H/P): Contact number (O): Contact number (O):


50 RESTRICTED

Appendix B

SCHOOL-BASED ASSESSMENT FOR PRACTICAL CHEMISTRY (PAPER 962/4) EXPERIMENT REPORT STPM 2014

Centre nu

Experiment Number Topic Problem/Modification/Suggestion/Comment

Note: If there is no problem/modification/suggestion/comment for a certain experiment, please wri NONE


51 RESTRICTED

Part 2 Practical Chemistry 2.1 Introduction 2.1.1 MEC has determined 13 compulsory experiments and one project to be carried out

by students which will be assessed by the teacher in three respective terms. 2.1.2 Experiments and project are to be carried out either individually or in groups as

recommended in the Table of Summary of Experiments and Project on pages 55. 2.1.3 The assessment of experimental skills should be done while the student is carrying out

the experiment and also on the student the project should be done according to the project report and the oral presentation made by students.

2.1.4 For a student who is absent for an experiment with reason, the teacher can fix another

date for the students to carry out the experiment. 2.1.5 Students may write their practical work and project reports in either English or Bahasa

Melayu. The practical work reports is to be submitted to the teacher on the same day the experiment is carried out unless otherwise stated. (Refer to the Table of Summary of Experiments and Project on pages 55). Practical work reports which are not submitted

2.1.6 Practical work reports which can be completed at home are to be submitted to the

teacher not later than 3 days from the date of the experiment. A penalty of 2 marks is to be imposed for the reports submitted late to the teacher. Practical work reports which are submitted lamark.

2.1.7 The teacher is required to set the dateline for the submission of project in the specified

date at the end of third term. A penalty of 2 marks is to be imposed for the reports submitted late to the teacher.

2.1.8 The oral presentation for the project work should be carried out by the teachers after the

assessment of the project report of all students. If the teacher suggests that changes are required towards the project report after the oral presentation, the student needs to correct the project report.

2.1.9 For a student who has transferred to another school, the previous school is to send the

Form which is partially completed and signed by the subject teacher, to the student

2.2 Assessment of Practical Work and Project 2.2.1 Students are to be assessed based on the following skills: Skill A: Use of techniques and manipulation of apparatus and materials To get maximum marks, students need to exhibit psychomotor skills in

manipulating the apparatus and materials skillfully and efficiently to a suitable degree of accuracy without assistance.


52 RESTRICTED

Skill B: Observations, measurements, and recording

To get maximum marks, students need to make observations accurately, record readings and data completely, and perform calculations to a suitable degree of accuracy.

Skill C: Interpretation of experimental observations and data

To get maximum marks, students need to answer all the questions given or make deductions correctly.

Skill D: Design and planning of investigation To get maximum marks, students need to plan their experiment or project neatly,

completely, and efficiently according to the format they have learned and to complete the experiment or project within a specified period of time and/or they are able to modify the planning based on their experience.

Skill E: Scientific and critical attitudes

Among the attitudes expected of students are self-reliant, trustworthy, fair, curious, inquisitive, having initiative, innovative, receptive to new ideas, cooperative, and caring for the environment.

Skill F: Oral presentation

itive and appropriate experiences in a wide range of ICT applications, and exhibit a good technique of presentation skills and communication skills.

2.2.2 The school will be notified of the theme of the project for the current year by MEC. The

students are free to propose the title of the project based on the theme given. 2.2.3

project report and oral presentation. Students will be assessed by the same skill which is assessed in the practical work.

2.2.4 The report on project which has been done on third term should have the following

format: (a) Title (b) Abstract (c) Introduction (d) Methodology (e) Observations, result and discussion (f) Conclusion (g) References/Bibliography


53 RESTRICTED

2.2.5 The assessment framework of the project work is shown in the table below.

Component Group Individual Total Project report 66.67 % 66.67%

Project file 10% 10%

Oral Presentation 13.33% 10% 23.33%

Total 100% 2.2.6 The written report should be at least 800 words and not more than 1500 words. The

the assessment criteria. 2.2.7 The oral presentation will be assessed individually and as a group. On the individual

level, each student is given a minimum of 5 minutes per student. For groups of three students, a maximum time limit of 20 minutes is allocated; whereas for groups of two students, the maximum limit is 15 minutes. The group presentation also includes those that do not exceed 5 minutes. Each presentation will have a Q & A session.

2.2.8 Students need to be aware that the written work they submit must be entirely their own and cite any source that had been referred to. Teachers should try to encourage students to take responsibility for their learning, so that they accept ownership of the work and take pride in it.


54 RESTRICTED

2.3 Table of Summary of Experiments and Project


Report to be

completed

First Term

1 Volumetric analysis

Stoichiometry To determine the exact concentration of a monobasic acid, HX


2 Acid base and redox

To determine the mass of sodium ethanedioate used to prepare a solution containing sodium ethanedioate and hydrated ethanedioic acid


3 Purity and stoichiometry

To determine the purity of a sample of sodium sulphite


4 Physical Quantity

Reaction kinetics To determine the effect of temperature on the reaction rate


5 Equilibrium and solubility

To determine the solubility product, Ksp, of MX2 and enthalpy change of solution, solH


Second Term

6 Physical Quantity

Thermochemistry To determine the heat of reaction


7 Electrochemistry- Faraday's Laws

To determine the percentage purity of copper metal by electrolysis



55 RESTRICTED


Report to be

completed


To determine the cations and anions of inorganic substances



To determine the cations and anions in inorganic salts



To determine the percentage of aluminium in a sample X by means of the preparation of a complex compound of aluminium with 8-hydroxyquinoline

Individually/Group

In the laboratory

Third Term


To study the reactions of alcohols and carbonyl compounds



To study the reactions of organic nitrogen compounds (amides, amines and their salts, amino acids and proteins)



To prepare a sample of 2-(4-hydroxyphenylazo) benzoic acid

Group At home

Project Volumetric analysis/ Physical quantity/

Technique

To enable students to acquire knowledge and skills in chemistry using ICT as well as to develop soft-skills

Group At the end of third term


56 RESTRICTED

2.4 Experiment for First Term Experiment 1 Topic: Volumetric analysis stoichiometry Purpose: To determine the exact concentration of a monobasic acid, HX Question: You are provided with a monobasic acid, HX, with a concentration in the range of

0.500 mol dm 3 to 1.00 mol dm 3. You are required to plan and carry out an experiment to determine the exact concentration of the HX solution provided.


57 RESTRICTED

Experiment 2 Topic: Volumetric analysis Acid base and redox Purpose: To determine the mass of sodium ethanedioate used to prepare a solution containing

sodium ethanedioate and hydrated ethanedioic acid Materials: KA 1 is a solution containing hydrated ethanedioic acid, H2C2O4.2H2O, and sodium

ethanedioate.

KA 2 is a solution containing 3.50 g potassium manganate(VII) per dm3.

KA 3 is a solution containing 1.70 g hydroxide ions per dm3. KA 4 is 1.00 mol dm-3 sulphuric acid.

Phenolphthalein is used as an indicator. Procedure: (a) Pipette 25.0 cm3 KA 1 into a titration flask. Add two or three drops of phenolphthalein

and titrate this solution with KA 3. Record your readings in the table below.

Repeat the titration at least two times to achieve accurate results. Results: (b) Record your titration readings in the table below.

Titration number

Rough

Accurate First Second Third

Final reading/cm3 Initial reading/cm3 Volume of KA 3/cm3

(i) Calculate your average titre value showing the suitable titre values that you use.

(ii) 25.0 cm3 of KA 1 3 of KA 3 for a complete reaction. (c) Pipette 25.0 cm3 of KA 1 into a titration flask. Then add 25 cm3 of KA 4. Heat this

solution to about 60 C, and titrate the solution with KA 2 until a faint pink colour persists in the solution.

Repeat the titration at least two times to achieve accurate results.


59 RESTRICTED

Results: (d) Record your titration readings in the table below.

Titration number

Rough

Accurate First Second Third


(i) Calculate your average titre value showing the suitable titre values that you use.

(ii) 25.0 cm3 of KA 1 3 of KA 2 for a complete reaction. Questions: (e) Calculate the concentration, in mol dm 3, of hydrated ethanedioic acid in KA 1 solution.

(f) Calculate the mass of ethanedioate ions, C2O42 , in 1.00 dm3 of KA 1.

(g) Calculate the concentration, in mol dm 3, of ethanedioate ions which originated from the sodium ethanedioate salt.

(h) Calculate the mass of sodium ethanedioate present in 1.00 dm3 of solution KA 1.

(i) Calculate the percentage of sodium ethanedioate in solution KA 1.

(j) Why was solution KA 4 added to solution KA 1 before the titration?


60 RESTRICTED

Experiment 3 Topic: Volumetric analysis Purity and stoichiometry Purpose: To determine the purity of a sample of sodium sulphite Materials: KA 1 is 0.050 mol dm 3 aqueous iodine.

KA 2 is 0.100 mol dm 3 aqueous sodium thiosulphate.

KA 3 is a solution containing 24.00 g of anhydrous sodium sulphite, Na2SO3, per dm3. KA 4 is 2 g sodium hydrogencarbonate.

Starch is used as an indicator. Introduction: The sulphite ion can be oxidised quantitatively to the sulphate ion by iodine in the presence of

the hydrogen carbonate ion.

SO32 + I2 + H2O SO4

2 + 2HI

2HI + 2HCO3

2I + 2H2O + 2CO2

If a solution of sodium sulphite is added to an excess of a standard solution of iodine, the excess iodine in the resulting solution can be titrated with a standard solution of sodium thiosulphate. Hence the concentration of sodium sulphite can be determined.

Procedure: (a) Pipette 50.0 cm3 of KA 1 into a titration flask. Using another pipette, place 25.0 cm3 of

KA 3 slowly into the titration flask containing KA 1 and shake. Add 2 g of KA 4 and shake the flask again. Titrate the resulting solution with KA 2 using starch as indicator.

Repeat the titration as many times as you think necessary to achieve accurate results. Results: (b) Record your titration readings in the table below.

Titration number

Rough

Accurate First


(i) Calculate your average titre value showing the suitable titre values that you used.

(ii) 50.0 cm3 of KA 1 3 of KA 2 for a complete reaction.


61 RESTRICTED

Questions: (c) Write a balanced equation for the reaction between iodine and the thiosulphate ion.

(d) Calculate the volume of I2 that did not react with the sulphite ions.

(e) Using your answer to (d), calculate the volume of I2 that reacted with the sulphite ions.

(f) Using your answer to (e),

(i) calculate the concentration, in mol dm 3, of the sulphite ions in solution KA 3,

(ii) calculate the mass of Na2SO3 present in 250 cm3 of KA 3. (g) Using your answer to (f)(ii), calculate the percentage purity of Na2SO3 that you used.


62 RESTRICTED

Experiment 4 Topic: Reaction kinetics Purpose: To determine the effect of temperature on the reaction rate Materials: KA 1 is 0.150 mol dm 3 potassium iodide solution.

KA 2 is 0.5% starch solution.

KA 3 is 0.050 mol dm 3 sodium thiosulphate solution.

KA 4 is 0.100 mol dm 3 hydrogen peroxide solution.

KA 5 is 0.100 mol dm 3 sulphuric acid. Procedure: (a) Pipette 25.0 cm3 of KA 1 into a conical flask. By means of a measuring cylinder, add

10 cm3 of KA 2 and 25 cm3 of distilled water to the solution. Then run in 10.00 cm3 of KA 3 from the burette. Record the temperature of the mixture in the table below.

Using a measuring cylinder, place 50 cm3 of KA 4 and 20 cm3 of KA 5 into a beaker. Transfer this mixture quickly into the conical flask above and immediately start the stopwatch. Swirl the conical flask regularly and record the time when the mixture turns blue. Note the time taken to the nearest second. If no colour appears after two minutes, repeat the procedure.

Repeat the experiment at the following temperatures: (i) 10 C below room temperature; (ii) 10 C above the room temperature and; (iii) 20 C above the room temperature. Results: (b) Record and complete your readings in the table below.

Mixture 1 2 3 4 Volume of KA 1/cm3 25.0 25.0 25.0 25.0

Volume of KA 2/cm3 10 10 10 10

Volume of distilled water/cm3 25 25 25 25

Volume of KA 3/cm3 10.00 10.00 10.00 10.00



Temperature, T/ C

Time, t/s

1/s1

t


63 RESTRICTED

Questions: (c) Why does the mixture in (a) turn blue?

(d) Plot a graph of t1

against T.

(e) From your graph, what could be the effect of temperature on the reaction rate?

(f) Using your graph,

(i) compare the rate of reaction at 30 C with the rate of reaction at 40 C,

(ii) give an explanation for your answer.


64 RESTRICTED

Experiment 5 Topic: Equilibrium and solubility Purpose: To determine the solubility product, Ksp, of MX2 and enthalpy change of solution,

solH

Materials:

KA 1 is 0.100 mol dm 3 of 2+M ion.

KA 2 is 0.500 mol dm 3 of X ion. Introduction: A compound MX2, which is slightly soluble in water, is formed when two solutions, one

containing 2+M ions and the other X ions, are mixed together. The compound will be

precipitated at the temperature of reaction when the value of the product 22+M X is greater

than the value of the solubility product, Ksp, of the compound and a saturated solution is formed. The chemical equilibrium of the compound in the saturated solution is represented by

MX2(s) 2+ (aq)M + 2 (aq)X Procedure:

(a) Transfer 12.00 cm3 of KA 1 from a burette into a boiling tube. Place thermometer in the boiling tube and titrate solution KA 1 with KA 2 from a second burette until the first appearance of the white precipitate. Record the temperature of the first appearance of the white precipitate and the volume of KA 2 used in the table below.

(b) Transfer 12.00 cm3 of KA 1 from a burette into a boiling tube. Place a thermometer in the boiling tube and from the second burette run 7.00 cm3 of KA 2 into it. Stir the saturated solution gently with the thermometer. Leave the boiling tube for a few minutes until the reaction has reached equilibrium.

Then place the boiling tube in a hot water bath at 75 °C 80 °C. Stir the saturated solution until all the precipitate has dissolved. Do not remove the thermometer from the solution.

Remove the boiling tube from the hot water bath and continue to stir the solution gently with the thermometer until the first appearance of white precipitate is observed. Record the temperature of the first appearance of the white precipitate in the table below. Wash and clean the thermometer for the next experiment. Repeat the experiment with different volumes of KA 2 as shown in the table below.


65 RESTRICTED

Results: (c) Record and complete your readings in the table below.

Experiment number

Volume of KA 1/cm3

Volume of KA 2/cm3

Temperature of the first appearance of

precipitate/°C

Solubility product, Ksp

1 12.00

2 12.00 7.00

3 12.00 9.00

4 12.00 11.00

5 12.00 13.00 Questions: (d) Calculate the solubility product, Ksp, of compound MX2 at each temperature recorded.

Record your results in the table above.

(e) Plot a graph of solubility product, Ksp, of compound MX2 against temperature.

(f) Use your graph to determine the solubility product of compound MX2 at 50 °C.

(g) The relationship between solubility product, Ksp, of a compound and temperature, T, in Kelvin is given by the equation

101

log constant2.303sp

HKR T

(i) From the results obtained in (d), calculate the enthalpy change of solution, solH for

the reaction

2 (s)MX 2+ (aq) + 2 (aq)M X

(ii) Is the reaction exothermic or endothermic? Explain your answer.


66 RESTRICTED

2.5 Experiment for Second Term Experiment 6 Topic: Thermochemistry Purpose: To determine the heat of reaction Materials: KA 1 is 2.00 mol dm 3 hydrochloric acid.

KA 2 is solid anhydrous sodium carbonate.

KA 3 is solid sodium hydrogencarbonate. Procedure: (a) Using a burette, run 30.00 cm3 of KA 1 into a plastic cup. Leave the cup with its contents

to stand for a few minutes, then record the temperature of the solution in the table below.

Weigh a stoppered test-tube containing KA 2 and record its weight in the table below. At one go, transfer all of the KA 2 into the plastic cup containing KA 1. Ensure that all solid leaving the test-tube enters the plastic cup and no liquid is lost through splashing. Stir the solution carefully with the thermometer, and record the highest temperature attained. Reweigh the empty test-tube and record its weight in the table below.

Repeat the above procedure using KA 3 to replace KA 2. Results: (b) Record all your readings and weights in the table below.

KA 2 KA 3

Weight of test-tube + solid/g

Weight of empty test-tube/g

Weight of solid/g

Final temperature of mixture/ C

Initial temperature of acid/ C

Temperature change/ C


67 RESTRICTED

Questions: (c) Assuming that the heat loss to the plastic cup, thermometer and surroundings can be

ignored and the specific heat capacity and density of all the solutions are 4.2 J g 1 K 1 and 1.0 g cm 3 respectively, calculate

(i) the heat change in the reactions involving KA 1 with KA 2 and KA 1 with KA 3,

(ii) the number of moles of anhydrous sodium carbonate and sodium hydrogencarbonate in KA 2 and KA 3 respectively,

(iii) the enthalpy change for the reactions of KA 2 and KA 3 with hydrochloric acid respectively.

(d) Write balanced equations for the reactions of KA 2 and KA 3 with hydrochloric acid.

(e) Draw an energy level diagram for the related reactions.

(f) Calculate H for the conversion reaction of sodium hydrogencarbonate to sodium carbonate using Hess Law and (e).


68 RESTRICTED

Experiment 7 Topic: Electrochemistry F Purpose: To determine the percentage purity of copper metal by electrolysis Question: You are required to plan and to carry out an experiment to determine the percentage purity of

copper metal by electrolysis.


69 RESTRICTED

Experiment 8 Topic: Qualitative analysis Purpose: To determine the cations and anions of inorganic substances Procedure: (a) Solids KA 1 and KA 2 are simple salts. Carry out the following experiments with

(i) solid KA 1 to identify its cation and anion,

(ii) solid KA 2 to identify its cations. In all the experiments, the reagent should be added gradually until no further change is

observed. Record your observations and the deductions you make from them in the spaces provided. Deduce what you can about KA 1 and KA 2. Observations should include details of colour changes, precipitates and tests on gases evolved, and you should indicate clearly at which stage in the test a change occurs.

Tests on KA 1

Test Observation Deduction

(b) Add dilute hydrochloric acid to a small amount of solid KA 1, then warm gently.

(c) Dissolve solid KA 1 in distilled water and filter. Use separate portions of the filtrate for tests (i) to (vi).

(i) Add aqueous sodium hydroxide, then in excess.

(ii) Add aqueous ammonia, then in excess followed by aqueous ammonium chloride.

(iii) Add aqueous iron(III) chloride, then warm.

(iv) Add aqueous silver nitrate followed by dilute nitricacid.

(v) Add aqueous disodium hydrogen phosphate.

(vi) Add aqueous potassium chromate(VI) followed by dilute hydrochloric acid.

Identity of KA 1: .................................


70 RESTRICTED

Tests on KA 2


(d) Dissolve all of solid KA 2 in distilled water and filter. Use separate portions of the filtrate for tests (i) to (v).

(i) Add aqueous sodium hydroxide, then in excess, and warm.

(ii) Add aqueous potassium iodide.

(iii) Add aqueous potassium chromate(VI).

(iv) Add aqueous sodium ethanoate, then warm.

(v) Add aqueous sodium carbonate, then warm.

Identity of cations present in KA 2


71 RESTRICTED

Experiment 9 Topic: Qualitative analysis Purpose: To determine the anions in inorganic salts Procedure:

(a) You are required to plan and carry out tests to identify the anions in a solid mixture KA 1. In all the tests, the reagent should be added gradually until no further change is observed.

Record your observations and the deductions you make from them in the spaces provided. Deduce what you can about the anions in KA 1. Observations should include details of colour changes, precipitates and tests on gases evolved, and you should indicate clearly at which stage in a test a change occurs.

Tests on KA 1



72 RESTRICTED


Identity of anions present in KA 1


73 RESTRICTED

Experiment 10 Topic: Technique Synthesis Purpose: To determine the percentage of aluminium in a sample X by means of the

preparation of a complex compound of aluminium with 8-hydroxyquinoline Materials: KA 1 is a solution of 8-hydroxyquinoline in ethanoic acid. KA 2 is 2 mol dm 3 aqueous ammonium ethanoate.

KA 3 is sample X.

KA 4 is 2 mol dm 3 hydrochloric acid. Introduction: Aluminium in a certain sample can be determined quantitatively by means of the process of

formation of complex compounds, for example, an alum complex is produced by the reaction of an alum with 8-hydroxyquinoline.

Procedure: (a) Weigh out accurately between 0.25 g and 0.30 g of KA 3. Record your readings in the

table below.

Mass of container + KA 3/g

Mass of empty container/g

Mass of KA 3/g

Place all of KA 3 into a 250 cm3 beaker, and add 150 cm3 of distilled water followed by

one drop of KA 4. Warm the mixture to a temperature between 60 C and 70 C. Then add 25 cm3 of solution KA 1, followed slowly by 50 cm3 of solution KA 2. A precipitate will be formed. Remove the beaker. Stir this solution for half an hour using a magnetic stirrer.

Weigh an empty crucible and record your readings in the table on the next page. Filter the solution above and wash the precipitate with cold distilled water. Transfer the precipitate into an empty crucible and dry the precipitate in the oven at about 120 C. Cool and weigh the crucible together with its contents.

Al3+ + 3 + 3H+


74 RESTRICTED

Results: (b) Record your readings in the table below.

Mass of crucible + precipitate/g

Mass of empty crucible/g

Mass of precipitate/g

Questions: (c) Explain

(i) why the mixture of solutions KA 1 and KA 2 needs to be stirred for half an hour using the magnetic stirrer,

(ii) why the complex precipitate is washed with cold water.

(d) How would you ensure that the complex precipitate obtained is completely dried?

(e) Calculate the mass of 1 mole of complex compound with the formula Al(C9H6NO)3 .

(f) Calculate the percentage of aluminium in the complex compound.

(g) Calculate the percentage of aluminium in sample X.


75 RESTRICTED

2.6 Experiment for Third Term Experiment 11 Topic: Qualitative analysis Purpose: To study the reactions of alcohols and carbonyl compounds Procedure:

(a) KA 1 is an alcohol and KA 2 is a carbonyl compound. Carry out the following tests to confirm the functional groups/structures present in these two compounds.

In all the tests, the reagents should be added gradually until no further change is observed. Record your observations and deductions you make from them in the spaces provided. Observations should include details of colour changes and precipitates formed.

Tests on KA 1


(b) Add 1 cm3 of glacial ethanoic acid to 1 cm3 KA 1 followed by 3 drops of concentrated sulphuric acid, then warm gently in a hot water bath. Cool and pour the resulting mixture into a beaker containing distilled water.

(c) Add 1 2 drops of acidified potassium manganate(VII) solution to 2 cm3 of KA 1 and heat gently.

(d) Place about 5 drops of KA 1 in a test tube and add 2 cm3 of distilled water. Shake the test tube until all the samples have dissolved. Add 1 cm3 of 2.5 mol dm 3 sodium hydroxide solution, and then slowly add the iodine potassium iodide solution, with shaking until the dark colour of iodine persists. Continue adding the iodine potassium iodide solution until the iodine colour is not discharged for 2 minutes at 60 °C.


76 RESTRICTED

Tests on KA 2


(e) Dissolve about 0.5 cm3 or 50 mg of KA 2 in 2 cm3 95% ethanol. Add 2 to 3 drops of this mixture into the test tube containing 3 cm3 of 2, 4-dinitrophenylhydrazine reagent. Shake the test tube and observe the formation of any precipitate. If no precipitate forms, immediately allow the mixture to stand for 5 10 minutes.

(f) Dissolve about 1 cm3 or 0.2 g of KA 2 in 5 cm3 distilled water and add 5 cm3

, shake the test tube and heat the mixture to boiling. Cool the mixture to room temperature.

(g) Add 2 3 drops or 0.1 g of KA 2 to be

reagent. Shake the test tube slowly and note the formation of silver mirror or precipitate. If there is no precipitate after 10 minutes, warm the mixture in a water bath at 30 °C for 5 to 10 minutes.

(h) Add 1 2 drops of acidified potassium manganate(VII) solution to 2 cm3 of KA 2 and heat gently.

(i) Place about 5 drops of KA 2 in a test tube and add 2 cm3 of distilled water. Shake the test tube until the samples have dissolved. Add 1 cm3 of 2.5 mol dm 3 sodium hydroxide solution, and then slowly add the iodine potassium iodide solution, with shaking until the dark colour of iodine persists. Continue adding the iodine potassium iodide solution until the iodine colour is not discharged for 2 minutes at 60 °C.

Remove the excess iodine by adding a few drops of 2.5 mol dm 3 sodium hydroxide solution, with shaking. Add equal amount of water and allow the mixture to stand at room temperature for 15 minutes.

Identity of functional group/structure in KA 2


77 RESTRICTED

Experiment 12 Topic: Qualitative analysis Purpose: To study the reactions of organic nitrogen compounds (amides and amines) Procedure:

(a) KA 1 and KA 2 are organic nitrogen compounds. Carry out the following tests to identify KA 1 and KA 2.

In all the tests, the reagents should be added gradually until no further change is observed. Record your observations and deductions you make from them in the spaces provided. Comment on the types of chemical reaction occurring and deduce the functional groups present in these compounds. Observations should include details of colour changes, precipitates, and tests on gases evolved, and you should indicate clearly at which stage in the test a change occurs.

Tests on KA 1


(b) (i) Add 2 cm3 of distilled water to about 0.1 g of KA 1 in a test tube and shake vigorously.

(ii) Then add 2 or 3 drops of Universal indicator.

(c) To about 0.1 g of KA 1 in a test tube, add 3 cm3 of 5% solution of sodium hydrogen carbonate and shake.

(d) Add 0.5 cm3 or 0.5 g of KA 1 to 1.5 cm3 of 4.5 mol dm 3 hydrochloric acid and cool the solution to 0 °C. Dissolve 0.5 g of sodium nitrite in 2.5 cm3 distilled water and add this solution drop wise, with shaking, to the cold solution. Then, transfer 2 cm3 of the solution to a clean test tube, warm gently, and identify for the gas evolved.

(e) Add about 1 cm3 dilute sulphuric acid to about 0.2 g of KA 1 in a test tube. Shake and heat the mixture in a hot water bath for 5 minutes.

Cautiously smell the vapour evolved/released.


78 RESTRICTED


(f) (i) Add 1 cm3 of sodium hydroxide solution to 0.4 g of KA 1 in a test tube. Shake and heat the mixture in a hot water bath for 5 minutes.

(ii) Acidify the mixture produced in (i) and heat the mixture in the hot water bath for 5 minutes.

Cautiously smell the vapour evolved/released.

Identity of KA 1: .............................................................................................................................


79 RESTRICTED

Tests on KA 2


(h) To about 2 drops of KA 2 in a test tube, add 2 cm3 of distilled water and shake vigorously.

Then, add 2 or 3 drops of Universal indicator.

(i) To about 10 drops of KA 2 in a test tube, add dilute hydrochloric acid and shake until dissolved. Then, add 2 cm3 of 0.5 mol dm 3 sodium hydroxide, shake and warm gently in a hot water bath.

(j) Add 0.5 cm3 or 0.5 g of KA 2 to 1.5 cm3 of 4.5 mol dm 3 hydrochloric acid and cool the solution to 0 °C. Dissolve 0.5 g of sodium nitrite in 2.5 cm3 distilled water and add this solution drop wise, with shaking, to the cold solution. Then, transfer 2 cm3 of the solution to a clean test tube, warm gently, and identify for the gas evolved.

(k) To about 10 drops of KA 2 in a test tube, add dilute hydrochloric acid and shake until dissolved. Then, add bromine water drop by drop. Shake gently.

If KA 2 has the relative molecular mass of 73.0, the identity of KA 2: ......................................


80 RESTRICTED

Experiment 13 Topic: Technique-Synthesis Purpose: To prepare a sample of 2-(4-hydroxyphenylazo)benzoic acid Materials: KA 1 is solid 2-aminobenzoic acid.

KA 2 is 1.70 mol dm 3 hydrochloric acid.

KA 3 is solid sodium nitrite.

KA 4 is a mixture of 0.30 mol dm 3 phenol and 1.35 mol dm 3 sodium hydroxide.

KA 5 is 4.00 mol dm 3 hydrochloric acid. Introduction: Azo dyes are easily prepared by the coupling of diazotised aniline with either a phenol or

aniline. In this experiment, 2-aminobenzoic acid is diazotised and coupled with phenol in an alkaline solution to give the salt of an azo dye. Acid is added to produce the azo dye of 2-(4-hydroxyphenylazo)benzoic acid.

COOH

NH2HNO2, HCl

<5 oC

COOH

N2Cl

COOH

N2Cl+

OH

1. NaOH2. H3O+

COOH

N OHN

Procedure: (a) Weigh out accurately 3.40 g of KA 1. Record your reading in the table below.

Mass of container + KA 1/g

Mass of empty container/g

Mass of KA 1/g Place KA 1 into a 125 cm3 conical flask, and add 60 cm3 of KA 2. Swirl and cool the

conical flask containing the mixture in an ice-water bath. In a 100 cm3 beaker dissolve 1.80 g of KA 3 in 15-20 cm3 of distilled water. Using a teat pipette, slowly add drop-wise the solution KA 3 to the ice-cold mixture in the conical flask, while swirling, over a time span of about 10 minutes. Maintain the temperature of the reaction mixture below 5 °C. Then, slowly pour the diazonium salt solution formed into a steadily swirled 500 cm3

conical flask containing 85 cm3 of ice-cold KA 4 in an ice-water bath.


81 RESTRICTED

Leave the resulting mixture aside for about five minutes. To this mixture, add 30 cm3 of KA 5 while swirling vigorously. Using a spatula, break up the lumps well. Filter the product formed by means of the suction filtration apparatus. Wash well the product in the Buchner funnel several times with distilled water and then/before leaving it under suction for about 10 minutes. Then, wash the product again with 100 cm3 of ice-cold mixture of acetone-water (1:1 v/v). Onto a large evaporating dish (of known weight), transfer and spread out the final product formed. Dry in an oven at 45 50 °C for three working days (total about 3 ! 8 hours = 24 hours). Cool, record the colour and weigh the evaporating dish together with its contents.

Results: (b) Tabulate your results. Questions: (c) Name the type of mechanism involved in the coupling of the diazonium salt with phenol.

(d) What is the main role of sodium hydroxide in this experiment?

(e) Why must the temperature during diazotisation be maintained below 5 C?

(f) Calculate the maximum mass of 2-(4-hydroxyphenylazo)benzoic acid that may be formed from the KA 1 used.

(g) Calculate the percentage of 2-(4-hydroxyphenylazo)benzoic acid produced in your experiment.


82 RESTRICTED

Project Theme: Investigating the chemical and/or physical properties of naturally occurring substances (a) Suggested natural products: (i) Leaves (ii) Fruits (iii) Flowers (iv) Roots (b) Suggested topics (students may also choose other relevant topics): (i) Acid-base indicators from natural dyes (ii) Vegetable dyes for clothing the effects of sunlight, heat and detergents (iii) Metal complexes of curcumin (iv) The stability of ascorbic acid/Vitamin C in fruit juices how it is affected by

conditions such as refrigeration, sunlight, microwaving or freshly squeeze (v) Do limes lose or gain Vitamin C after being pickled (vi) Pigment separation using paper chromatography (c) Suggested methods of analysis (students may also choose other relevant methods): (i) Volumetric analysis (ii) Chromatography (iii) pH (iv) Solvent extraction (v) Distillation General purpose of the project (a) To inculcate awareness for healthy living (b) To instil good moral values cooperation, independence and self confidence (c) To apply basic scientific skills in their research project (d) To apply the basic chemical principles and techniques in their investigation Procedure: (a) Students are divided into groups of three to four and headed by a leader. (b) The group should identify a research topic that is relevant to the theme. (c) Students should set research objectives, working plan and techniques to be carried out.

They are encouraged to use available apparatus and instruments. (d) Students should consult and obtain approval from their teacher before carrying out the

research. (e) Students should keep a log book of their research activities and document all

observations, data analysis and results. (f) In carrying out their research, students are also encouraged to gather, process and present

information to describe and explain evidence for the need to monitor levels of contaminants/additives in consumer products. Information gathered can be from interview, survey and official sources.

(g) Students should state the conclusions and references used. (h) Students should prepare a well structured, clear, concise and precise research report.

manual chemistry 2014

Documents

practical science assessment

practical skills

chemistry practical

project assessment guide

direct assessment

recording of assessment

students manual

stpm chemistry subject