MC 17 C - 5. 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. Choose from the following list of substances, as to what matches the description from to (v) given below [propene, ethene, ethyne, substitution, addition, ethanol, methanol, vinegar, formic acid] The second member of the alkene series. Product of pyrolysis of methane at C. The type of reaction undergone by alkynes. The IUPAC name of the compound with condensed structural formula CH 3 CH 2 OH. (v) The common name of methanoic acid. (v) What would you observe in each of the following cases: Ammonium hydroxide is first added in a small quantity and then in excess to a solution of ferric chloride. Ammoniacal cuprous chloride solution is added to acetylene. Concentrated sulphuric acid is added to hydrated copper sulphate solution. Concentrated nitric acid is added to silver nitrate solution. Fill in the blank from the choices given below: In a molecule of chlorine there is presence of (single/double) covalent bond. Non-metals have (low/high) electron affinity. Down the group, the ionization potential (increase/decrease) Ionic compounds are (soluble/insoluble) in organic solvents. Elements of groups I A are strong (reducing/oxidising) agents. (d) Calculate the volume of 176 g of CO 2 at STP (atomic mass of C = 12 and O = 16) State Gay-Lussac s law of combining volumes. How many moles of Sulphur dioxide are present in 192 g of it? Calculate the volume of Oxygen required for the complete combustion of 13.2 g of propane (C 3 H 8 ) (atomic mass of C = 12, O = 16, H = 1) (e) Select the correct answer from the choices given: Which of these is not an ore of Zinc a) Calamine b) Cryolite c) Zincite d) Zinc blende Which of the following is not an amphoteric oxide a) CaO b) Al 2 O 3 c) PbO d) ZnO 242

2 MT EDUCARE LTD. X - ICSE (Chemistry) (v) In the periodic table halogens are placed in group a) 1 b) 17 c) 18 d) 2 The functional group present in acetone is a) Aldehydic b) Carboxyl c) Hydroxyl d) Ketonic When Concentrated hydrochloric acid is added to potassium permanganate, the gas evolved is a) Oxygen b) Chlorine c) Carbon dioxide d) Nitrogen dioxide (f) Name the law/terms/process defined as follows : The proce ss by which me tals containing impuritie s are purifie d electrolytically. Under the same conditions of temperature and pressure equal volume of all gases contains the same number of molecules. Acids containing hydrogen and a non-metallic element other than Oxygen. The substance added to the ore to get rid of the gangue. (v) The process of concentration of the bauxite ore using concentrated solution of sodium hydroxide. (g) Write the balanced chemical equation for each of the following reactions : Zinc is heated with Sodium hydroxide solution. Calcium chloride solution is added to sodium carbonate solution. Dilute Sulphuric acid is added to Zinc oxide. Catalytic hydrogenation of ethene. (v) Catalytic oxidation of ammonia. (h) Give reasons as to why : Ethanol can be converted to ethene using concentrated Sulphuric acid. An aqueous solution of ammonia acts as a weak base. Chlorofluorocarbons are a cause of ozone depletion. The blue colour of aq. Copper sulphate does not change when it is electrolysed using copper electrode. (v) Ferric chloride is stored in air tight bottles. Question 2. (a) SECTION - II (Attempt any four questions) List 1 contains metal alloys 1, 2, 3, 4 and 5 and the list 2 contains their uses A, B, C, D and E. Copy and complete the following table. Writing down the letter for correct use of each metal/alloy. An answer may be used once. 243

3 X - ICSE (Chemistry) MT EDUCARE LTD. List 1 Metal/alloy List 2 Uses 1 Zn A electrical fittings 2 Brass B Aircarfts 3 Aluminium C Galvanising 4 Duralumin D Fuse 5 Solder E transmission wires Give reasons for the following observations with regard to Hall Heroult s process: Electrolytic mixture is covered with coke or saw dust. The graphite anodes are continuously replaced. Cryolite and fluorspar are added to pure alumina. Give two points of difference between roasting and calcination. [3] Question 3. (a) Answer the following: A hydrocarbon contains 17.2% hydrogen. If the vapour density is 29, calculate it s molecular formula. What is the IUPAC name of the compound you obtained in Draw the structures of the possible isomers of the compound obtained in. Is this compound an alkane or an alkyne? (v) What type of isomerism is exhibited by the above compound? Question 4. (a) Study the diagram given below and answer the questions that follow: Name A and B What is the colour of the flame? What does this experiment show? Give a balanced chemical equation for the above experiment? Cotton wool B A Which property of sulphuric acid is depicted in the reaction given below: Cu + 2H 2 (conc.) Cu + 2H 2 O + SO 2 HCOOH H2SO(conc.) 4 CO + H 2 O 2P + 5H 2 (conc.) 2H 3 PO 4 + 2H 2 O + 5 SO 2. o NaCl + H 2 SO 200 C 4 NaHSO + HCl 4 (v) Na 2 CO 3 + H 2 (dil.) Na 2 +H 2 O + SO 2 244

4 MT EDUCARE LTD. X - ICSE (Chemistry) Question 5. (a) Solution P is a strong acid. Solution Q is a weak acid. Solution R is a strong alkali. Which solution contains solute molecules in addition to water molecules? Which solution will give a dirty green ppt with ferrous sulphate solution? Which solution could be a solution of glacial acetic acid? Give an example of a solution which is a weak alkali. Classify the following as deliquescent, hygroscopic or efflorescent salt. Calcium oxide Washing Soda Anhydrous calcium chloride Epsom salt Mention the colour changes observed when the following indicators are added to acids: Alkaline phenolphthalein solution. Methyl orange solution. Question 6. (a) Draw the branched structural formula of the following organic compounds whose IUPAC names are given below: 2, 2 dimethyl propane But - 2- yne. Answer the following questions with respect to the schematic representation given below: X + HBr CH 3 CH 2 Br + KOH (aq) Boil Y + KBr + CH 3 COOH Conc. H 2 (Z) + H 2 O What is the name of X, Y and Z respectively? What is the name given to the process of formation of (Z) from Y? Determine the percentage of oxygen in ammonium nitrate (Atomic Mass : N = 14, O=16) (d) Give the electron dot representation of NH 3 N 2 Question 7. (a) State process of preparation of salts are listed below 245

5 X - ICSE (Chemistry) MT EDUCARE LTD. (d) Titration Precipitation Direct Combination Simple Displacement Match the methods with the given salts Iron (III) Chloride Sodium Chloride Lead Sulphate Zinc Sulphate Name the products formed at the anode when the following are electrolysed. Acidulated water Molten lead bromide Correct the following statement. Sulphuric acid is an oxidizing agent. Potassium nitrate gives NO 2 and O 2 on heating. Define: Electro negativity. Coordinate covalent bond. 246