TEKNIK MENJAWAB SOALAN

CHEMISTRY PAPER 3SPM 4541/3

FORMAT OF PAPER 3TIME : 1 hr 30 minMARKS : 50 marksCONSTRUCT TESTED :

Science Process Skills (16 aspects)Task : Answer all 2 or 3 questionsLevel of difficult : L : M : H = 5 : 3 : 2

Scoring for item

• 3 marks – excellent : The best response• 2marks – Satisfactory : An average response • 1 mark- Weak : An inaccurate response• 0 mark – No response or Wrong response

1. Structure questions (45 minutes)

• Making observation • Inference • Identify and controlling the variables • Hypothesis• Classifying• Making operational definition• Reading instruments/measurement• Predicting• Interpreting data

2. Extended Response Item (45 min)

• Stating Aim, problem statement, hypothesis• Listing the variables, apparatus &

materials• Writing the procedures• Tabulation of data

Guide on answering

1. Answering structure question- quite similar to the structure question in section A paper 2, but emphasises on the process skills- application of the concepts and the theories related to the questions.

Guide on answering2. Extended response item (planning/ designing

experiment )- NO NEED to give complete report, this is only planning stage.- procedure is preferably in active form . (although the passive form is accepted) - normally the question requires:

Aim/problem statement hypothesis, All the variables, apparatus & materials Procedures Tabulation of data

Guide on answering

• Bilingual answer• Grammatical errors are ignored• Avoid use American spelling

(oxidise/oxidize???, colour/color????/)• Wrong spelling – often ignored• Avoid using abbreviation (short form)• List of substances and apparatus ( write

separately)

MATERIALS1. State the physical state of substances used

- sodium hydroxide solution, magnesium oxide powder, zinc powder, oxygen gas

2. State the correct quantity(a) Volume

[20-200cm3 HCl] → 100cm3

(b) Mass (solid) [ 2-5 g zinc power]

(c) concentration [0.5-2.0 mol dm-3] → 1.0 mol dm-3

Guide on answering

• Making observation –in paper 3, observation is drawn from SIGHT only.

• Graph – show axes with arrowhead, with correct labels, correct units, correct shape (line or curve).

• Diagram for set-up of apparatus – not required but encourage.

• Constructing table

Guide on answering

• Accuracy in taking measurement- depends on the instrument

• Calculation- Formula should use common symbol- eg. H = mcθ- correct unit must be stated- steps must be shown clearly

Guide on answering

• Variables - manipulated variable : 1 only- responding variable : 1 only- fix variable : more than 1

• Hypothesis :- ……………..MV, ……………..RV- when the temperature of reactant increases, the rate of reaction increases.

• Operational definition : what you observe (MV)

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