MC 17 C SECTION - I (40 marks) Compulsory : Attempt all questions from this section.

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1 Question 1 (a) SECTION - I (40 marks) Compulsory : Attempt all questions from this section 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 Gas produced by the action of dilute Sulphuric acid on Zinc Gas produced by the action of concentrated Nitric acid on Zinc A base but not an alkali An acid which is used to prepare Aqua Regia Dehydrating agent State one observation for each of the following: Copper Sulphate solution is stored in a Zinc vessel Ammonia gas is burned in oxygen in the absence of a catalyst Fused lead bromide is electrolysed Concentrated HCl is added to K Cr O 7 Warm water trickles on aluminium nitride Chlorine combines with excess of ammonia to form ammonium chloride and nitrogen, according to the equation: 8NH Cl 6NH 4 Cl + N (g) Calculate the minimum volume of Ammonia required to completely react with 1 litres of Chlorine Calculate the percentage of Chlorine in CaCl 6H O [Ca = 40, Cl = 355, H =1, O = 16] (d) Match the columns : A B A substance that turns moist starch iodide a) Ammonium Sulphate paper blue black A compound which releases reddish brown gas b) Lead Carbonate on reaction with Conc Sulphuric acid and copper A solution of this compound gives a dirty green ppt with Sodium hydroxide A compound that on heating with Sodium hydroxide produces a gas which forms dense white fumes of Hydrogen Chloride c) Chlorine d) Ferrous Sulphate 86 A white solid which gives a yellow residue e) Copper Nitrate on heating

2 MT EDUCARE LTD (e) Give the IUPAC names for the following: CH CH CH = CH (A) 3 (B) (C) CH OH 3 CH CH CH CH 3 3 CH 3 3 H CH CH CH C = O (f) (g) (h) Give the structural formula for the following: (A) 1, 1,, tetrabromoethane (B) 3 bromo methyl butanoic acid (C) chloropropanal Give reasons for the following: Alkynes are more reactive compared to their corresponding alkanes HCl gas conducts electricity in water but not in toluene Ionisation potential increases across a period Aluminium is used in thermite welding Choose the correct answer from the options given below: 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 The catalytic oxidation of Ammonia yields (A) NO (B) NO (C) N O (D) N A carbonate that does not decompose on heating (A) Lead carbonate (B) Copper Carbonate (C) Sodium carbonate (D) Zinc carbonate The covalent oxide (A) Al (B) S (C) MgO (D) CaO The process by which ions get discharged as neutral atoms at the anode during electrolysis (A) Reduction (B) Oxidation (C) Ionisation (D) Dissociation Give balanced equations for the following: Nitrosyl Chloride from concentrated Hydrochloric acid Sodium zincate from zinc Ethyne from Calcium Carbide Dilute Sulphuric acid and Sodium Sulphide Ammonia gas passed over heated Copper Oxide SECTION - II (40 Marks) (Attempt any four questions) Question (a) With reference to the electrolysis of acidulated water, answer the following: 87

3 MT EDUCARE LTD + B C + D A 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 A cylinder can hold 56 g of Hydrogen gas at STP Calculate: The amount of Sulphur dioxide gas it can hold at STP The volume of Sulphur dioxide gas at STP [S = 3, O = 16] Draw the electron dot diagram to depict the formation of: Magnesium oxide from 4 1 Mg and 16 8 O Question 3 (a) The distribution of electrons in the atoms of three elements in given below: X Y Z 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 Between two atoms of X Between the atoms of X and Z (Give formula) Between the atoms of Y and Z Copy and complete the following table : Alloy Major Metal Present Other Elements present One use Fe Ni, Cr, C Brass Duralumin (vi) (vii) (vii) 88

4 MT EDUCARE LTD Give a term in each case that befits the following descriptions: Organic compounds formed when alcohol reacts with a carboxylic acid in the presence of concentrated H SO 4 The combining of simple molecules to form large molecules at high temperature and pressure 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 SO Name the catalyst used in the above reaction Give the balanced chemical equation for the oxidation of SO The product of catalytic oxidation is not directly absorbed in water In which other compound is the oxidation product dissolved Give the chemical equation for conversion of oleum into Sulphuric acid The following diagram represents the set up after carrying out the brown ring test State the purpose of the brown ring test Name the chemical constituent of the brownring Y X Y Z Brown Ring Test Distinguish between the compounds using test given in the brackets: Ammonium chloride and Sodium chloride (alkali) Copper (II) oxide and Manganese (IV) oxide (concentrated HCl) Dilute HN and concentrated HN (copper) Zinc Nitrate and Lead Nitrate (NH 4 OH solution) Question 5 (a) A compound contains 45% carbon, 666% hydrogen and 5333% oxygen Its vapour density is 30 Calculate its empirical formula and molecular formula State Avagadro s Law What do you understand by the term glacial acetic acid Hydrogen Chloride gas is dissolved in water to get Hydrochloric acid by using a special funnel arrangement as shown in the adjacent figure Explain giving two points why is the adjacent device used HCl (gas) water 89

5 MT EDUCARE LTD (d) Write balanced chemical equations for the preparation of the following salts (as a major product) starting from IRON and using only the another substance Iron (III) chloride Iron (II) sulphate Iron (II) sulphide Question 6 (a) Quick lime CaO is obtained by burning limestone (CaC ) and the reaction is represented as given below: CaCO 3 CaO + CO What mass of limestone should be heated to obtain 11 kilograms of quicklime (At weight of Ca = 40, O = 16, C = 1) A metal M is to be extracted from its Sulphide ore Name the most suitable method for concentration of its ore A method for conversion of ore to its oxide Four elements P, Q, R, S have the following electronic configuration K L M P 8 7 Q 8 4 R 1 S 5 Which of the following P, Q, R, S is: Metallic A halogen Trivalent Similar in properties of carbon Write the formula of Sulphate of R Question 7 (a) Carry out the following Organic conversions: Prepare ethanol from chloroethane Dehydration of ethanol Prepare ethane from Sodium propionate Ethanol to Sodium ethoxide Ethene to ethanol How does liquor ammonia differ from liquid ammonia? Give one use of each By which process is Al H O converted to Al? 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 impractical method of preparing lead sulphate Explain [1] 90