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

Question 1.(a) Write balanced reactions(i) Prepare 1, 2 Dibromo ethane.(ii) Reduction of black coloured base with the basic gas.(iii) Oxidation of copper using dilute nitric acid.(iv) Convert the two monobasic strong acids to nitrosyl chloride.(v) Prepare dibasic strong acid using a non metal.

(b) What happens when(i) Acetylene is bubbled in ammoniacal cuprous chloride solution?(ii) First little and then excess of ammonium hydroxide solution is added to copper

sulphate solution?(iii) Hydrochloric acid is added to silver nitrate solution?(iv) Concentrated sulphuric acid is added to sugar crystals?(v) Hydrogen sulphide comes in contact with moist lead acetate paper?

(c) Name the gas liberated(i) On catalytic oxidation of ammonia.(ii) On thermal decomposition of the nitrate with no residue on heating.(iii) When calcium carbide is treated with water.

(d) Write the IUPAC name of the organic compound.(i) Obtained on oxidation of methane in presence of MoO.(ii) neo-pentane.

(e) Choose from A, B, C or D the statement which is not true for the following(i) Metals are elements which

(a) Are capable of forming ionic and covalent compound.(b) Have low ionization potential.(c) Reduce other elements and are oxidized to cations.(d) Are mono-atomic in nature.

(ii) In Ostwald’s Process(a) Platinum or Vanadium Pentoxide is used as catalyst.(b) NO is used as raw material.(c) The absorption tower is filled with quartz.(d) The main product is nitric acid.

(iii) MnO2 + 4HCl MnCl2 + 2H2O + Cl2(a) HCl used is concentrated.(b) This helps to differentiate between CuO and MnO2.(c) Mn4+ is reduced to Mn2+.(d) The colour changes from black to blue.

(iv) Across a period from left to right(a) Non metallic character increases (b) Valency remains the same(c) Number of shells remains the same (d) Basic oxides become acidic oxides

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(v) Solder is an alloy(a) Of Pb and Zn (b) Used in electrical fuse(c) Has low melting point (d) Used in welding

(f) Give reasons :(i) Metallic character increases down the group(ii) Nitric acid does not give rise to acid salts.(iii) Liquid HCl is a non conductor of electricity(iv) Bromine in CCl4 is used to differentiate between ethane and propyne

(g) Name the term defined :(i) The process of coating iron with zinc(ii) The process in which the mixture of aluminium powder and ferric oxide is

used to join broken iron griders.(iii) The process in which an organic acid react with an alcohol to give salt and water.

(h) 100ml of H2S reacts with 60ml of oxygen according to the reaction2H2S + O2 2H2O + 2S [H = 1, S = 32, O = 16 ] Find.

(i) the volume of oxygen used (ii) the mass of sulphur

(i) With the help of reactions prove that(i) Red lead is an oxidising agent(ii) Ethene is an unsaturated hydrocarbon(iii) Dilute nitric acid is a better oxidising agent than concentrated nitric acid.

(two reactions)

(j) State the colour of :(i) Potassium mercuric iodide with dissolved ammonia(ii) The residue obtained on thermal decomposition of the nitrate which

decrepitates on heating

(k) Define :(i) Avogadro’s law (ii) Electron affinity

(l) Give a chemical test to differentiate between the following pairs(i) Sodium carbonate and sodium sulphite(ii) Dilute nitric acid and dilute sulphuric acid(iii) Solution containing zinc ions and solution containing lead ions

SECTION - II(Attempt any four questions)

Question 2.

(a) Which of the methods A, B, C, D or E is generally used for preparing thechlorides listed below from (i) to (v)(A) Action of an acid on a metal(B) Action of an acid on an oxide or carbonate(C) Direct combination(D) Titration(E) Precipitation

(i) Copper (II) chloride (ii) Iron (II) chloride(iii) Iron (III) chloride (iv) Lead (II) chloride(v) Sodium chloride

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(b) In aluminium extraction state the use of(a) Adding cryolite to the electrolytic mixture(b) Sprinkling coke over the electrolytic mixture(c) Replacing the anode periodically.

(c) Write balanced equation to convert the given reducing agent to the requiredmetal(a) Basic gas to the metal used to make radiation sheath.(b) Combustible gaseous compound to the metal present in all steel.

Question 3.(a) Using an alkali write balanced reactions to prepare

(1) Ethylene (2) Acetylene(3) Methane

(b) Write the formula of :(i) the precipitate formed when ethyne is bubbled in ammoniacal silver nitrate

solution.(ii) the compound dehydrated to give ethene.(iii) the ester obtained on action of methanol on acetic acid.

(c) Define :(1) Isomers (2) Hydrocarbons

(d) Draw the structural formula of :(1) Ethanal (2) 2– Chloro – 1 – butene

Question 4.(a) A ring is electroplated with silver(i) Name the electrolyte used.(ii) What is the cathode and anode made up of ?(iii) Write the electrode reaction.

(b) In the Contact process write the catalytic reaction. What is the product obtainedwhen acid anhydride of sulphuric acid is dissolved in the acid to be prepared ?

(c) Do as directed :(i) Arrange Na, Cs, Fr, Li, K in decreasing order of ionization potential(ii) Of Zn, Pb, Fe, Ca choose one

(a) which produces two coloured ions ?(b) whose salt solution produces a precipitate which is soluble in both NaOH

and NH4OH ?

Question 5.(a) A compound contains 9.91% of potassium, 25.54% of mercury and 64.55% of

iodine. Find the empirical formula of the compound and write its commonname. [K = 39, Hg = 201, I = 127]

(b) 0.6 mole of copper sulphate weighs 96g at STP. If Cu = 64 S = 32 O = 16 H = 1find the gram molecular weight of copper sulphate, state if the given compoundchanges colour if heated or if it comes in contact with moisture.

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(c) A mixture of hydrogen and chlorine occupying 36 cm3 was exploded. Onshaking it with water 4 cm3 of hydrogen was left behind. Find the compositionof the original mixture.

Question 6.(a) Give reasons :(i) An optimum temperature of 450 – 500º C is used in the Haber’s process.(ii) Dilute nitric acid does not behave as a typical acid.(iii) Metallic character decreases across a period.(iv) Bauxite is concentrated by using saturated solution of sodium hydroxide.

(b) Nitric acid when dropped in water produces a conducting solution. Draw thestructure of the positively charged ion

(c) Name the following :(i) The property of H2SO4 which contributes to its dehydrating nature.(ii) The element obtained on action of HCl on sodium thiosulphate.(iii) The insoluble salt soluble in excess of liquor ammonia.(iv) The ion other than ammonium ion formed when ammonia dissolves in water.(v) The process of concentrating zinc blende.

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