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SECTION - I (40 marks)Compulsory : Attempt all questions from this section.

Question 1.(a) Select from the list given below (A to G), only one in each case which

matches with the description given below:(A) Hydrochloric acid (B) Hydrogen (C) Sulphuric acid(D) Copper Hydroxide (E) Nitrogen dioxide (F) Nitric oxide(G) Potassium hydroxide

(i) Gas produced by the action of dilute Sulphuric acid on Zinc.(ii) Gas produced by the action of concentrated Nitric acid on Zinc.(iii) A base but not an alkali(iv) An acid which is used to prepare Aqua Regia(v) Dehydrating agent.

(b) State one observation for each of the following:(i) Copper Sulphate solution is stored in a Zinc vessel(ii) Ammonia gas is burned in oxygen in the absence of a catalyst(iii) Fused lead bromide is electrolysed.(iv) Concentrated HCl is added to K2Cr2O7.(v) Warm water trickles on aluminium nitride.

(c) (i) Chlorine combines with excess of ammonia to form ammonium chlorideand nitrogen, according to the equation:8NH3 + 3 Cl2 6NH4Cl + N2 (g)Calculate the minimum volume of Ammonia required to completely reactwith 21 litres of Chlorine.

(ii) Calculate the percentage of Chlorine in CaCl2.6H2O[Ca = 40, Cl = 35.5, H =1, O = 16]

(d) Match the columns :A B

(i) A substance that turns moist starch iodide a) Ammonium Sulphatepaper blue black

(ii) A compound which releases reddish brown gas b) Lead Carbonateon reaction with Conc. Sulphuric acid and copper

(iii) A solution of this compound gives a dirty green c) Chlorineppt with Sodium hydroxide

(iv) A compound that on heating with Sodium d) Ferrous Sulphatehydroxide produces a gas which forms densewhite fumes of Hydrogen Chloride

(v) A white solid which gives a yellow residue e) Copper Nitrateon heating

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(e) (i) Give the IUPAC names for the following:(A) 3 2 2CH CH CH = CH

(B)

3

3 3

CH OH | |CH CH CH CH

(C)

3

3 2

CH H | |CH CH CH C = O

(ii) Give the structural formula for the following:(A) 1, 1, 2, 2 – tetrabromoethane(B) 3 – bromo – 2 – methyl butanoic acid(C) 2 – chloropropanal

(f) Give reasons for the following:(i) Alkynes are more reactive compared to their corresponding alkanes.(ii) HCl gas conducts electricity in water but not in toluene.(iii) Ionisation potential increases across a period.(iv) Aluminium is used in thermite welding.

(g) Choose the correct answer from the options given below:(i) A compound which has vapour density 13 and forms a red coloured ppt

when treated with Ammonical Copper (I) Chloride solution.(A) Ethene (B) Ethyne (C) Ethane (D) Methane

(ii) The catalytic oxidation of Ammonia yields.(A) NO (B) NO2 (C) N2O (D) N2

(iii) A carbonate that does not decompose on heating(A) Lead carbonate (B) Copper Carbonate(C) Sodium carbonate (D) Zinc carbonate

(iv) The covalent oxide(A) Al2O3 (B) SO3(C) MgO (D) CaO

(v) The process by which ions get discharged as neutral atoms at the anodeduring electrolysis(A) Reduction (B) Oxidation(C) Ionisation (D) Dissociation

(h) Give balanced equations for the following:(i) Nitrosyl Chloride from concentrated Hydrochloric acid.(ii) Sodium zincate from zinc(iii) Ethyne from Calcium Carbide(iv) Dilute Sulphuric acid and Sodium Sulphide.(v) Ammonia gas passed over heated Copper Oxide.

SECTION - II (40 Marks)(Attempt any four questions)

Question 2.(a) With reference to the electrolysis of acidulated water, answer the following:

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a) What is the solution marked by A?b) Give the name of electrode maked by D?c) What are the products marked by B and C?d) Give the electrolytic reaction occuring in the solution.e ) For the acidification of water which of these is preferred and why?

Dilute sulphuric acid or dilute nitric acid.

(b) A cylinder can hold 5.6 g of Hydrogen gas at S.T.P.Calculate:(i) The amount of Sulphur dioxide gas it can hold at S.T.P

(ii) The volume of Sulphur dioxide gas at S.T.P [S = 32, O = 16]

(c) Draw the electron dot diagram to depict the formation of:

Magnesium oxide from 2412Mg and 16

8O

Question 3.(a) The distribution of electrons in the atoms of three elements in given below:

In answering the following questions, you are not required to identify the atoms.You may write X, Y and Z as symbols for the elements.In each, state whether the bonding is ionic or covalent.(i) Between two atoms of X(ii) Between the atoms of X and Z (Give formula)(iii) Between the atoms of Y and Z.

(b) Copy and complete the following table :

Alloy Major Metal Present Other Elements present One use

(i) _________ Fe Ni, Cr, C (ii) __________

Brass (iii)______________ (iv) ______________ (v) __________

Duralumin (vi) ______________ (vii) _____________ (vii) __________

+

+ –

–

A

B C

D

62

X

82

82

Y Z

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(c) Give a term in each case that befits the following descriptions:(i) Organic compounds formed when alcohol reacts with a carboxylic acid in

the presence of concentrated H2SO4

(ii) The combining of simple molecules to form large molecules at hightemperature and pressure.

(iii) Organic compounds formed by the hydrogenation of alkenes.

Question 4.(a) With reference to the manufacture of Sulphuric acid by the CONTACT

process, one step is the catalytical oxidation of SO2.(i) Name the catalyst used in the above reaction.(ii) Give the balanced chemical equation for the oxidation of SO2.(iii) The product of catalytic oxidation is not directly absorbed in water. In

which other compound is the oxidation product dissolved.(iv) Give the chemical equation for conversion of oleum into Sulphuric acid.

(b) The following diagram represents the set up aftercarrying out the brown ring test.

(i) State the purpose of the brown ring test.(ii) Name the chemical constituent of the brownring ‘Y’.

(c) Distinguish between the compounds using test given in the brackets:(i) Ammonium chloride and Sodium chloride (alkali)(ii) Copper (II) oxide and Manganese (IV) oxide (concentrated HCl)(iii) Dilute HNO3 and concentrated HNO3 (copper)(iv) Zinc Nitrate and Lead Nitrate (NH4OH solution)

Question 5.(a) A compound contains 45% carbon, 6.66% hydrogen and 53.33% oxygen. Its

vapour density is 30. Calculate its empirical formula and molecular formula.

(b) (i) State Avagadro’s Law.(ii) What do you understand by the term ‘glacial acetic acid’.

(c) Hydrogen Chloride gas is dissolvedin water to get Hydrochloric acid byusing a special funnel arrangementas shown in the adjacent figure.Explain giving two points why is theadjacent device used.

‘X’‘Y’‘Z’

Brown Ring Test

water

HCl (gas)

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(d) Write balanced chemical equations for the preparation of the following salts (asa major product) starting from IRON and using only the another substance.(i) Iron (III) chloride(ii) Iron (II) sulphate(iii) Iron (II) sulphide

Question 6.(a) Quick lime CaO is obtained by burning limestone (CaCO3) and the reaction is

represented as given below:

CaCO3 CaO + CO2

What mass of limestone should be heated to obtain 112 kilograms of quicklime.(At weight of Ca = 40, O = 16, C = 12)

(b) A metal ‘M’ is to be extracted from its Sulphide ore.(i) Name the most suitable method for concentration of its ore.(ii) A method for conversion of ore to its oxide.

(c) Four elements P, Q, R, S have the following electronic configuration.

Which of the following P, Q, R, S is:(i) Metallic (ii) A halogen(iii) Trivalent (iv) Similar in properties of carbon(v) Write the formula of Sulphate of R.

Question 7.(a) Carry out the following Organic conversions:(i) Prepare ethanol from chloroethane.(ii) Dehydration of ethanol.(iii) Prepare ethane from Sodium propionate.(iv) Ethanol to Sodium ethoxide.(v) Ethene to ethanol.

(b) How does liquor ammonia differ from liquid ammonia? Give one use of each.

(c) (i) By which process is Al2O3 . 2H2O converted to Al2O3?(ii) Name the chemicals added to pure alumina at the time of electrolytic

reduction.

(d) The direct addition of dilute Sulphuric acid to lead carbonate is an impracticalmethod of preparing lead sulphate. Explain.

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