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. Choose from the following list of substances, as to what matches the description from to given below : [Bronze, lead (II) chloride, sodium chloride, Iron (III) chloride, brass, calcium carbonate] A compound which is deliquescent. A compound which is insoluble in cold water but soluble in hot water. The substance is an alloy of Zn, Cu and tin. A compound whose aqueous solution is neutral in nature. The flux used in the extraction of iron from hematite. (vi) (vii) (viii) (ix) Select the correct answers from the choices a, b, c, d which are given. Write down only the letter corresponding to the correct answer. During electrolysis of molten lead bromide which of the following takes place. (a) Bromine is released at the cathode. Lead is deposited at the anode. (c) Bromine ion gain electrons. (d) Lead is deposited at the cathode. Organic compound mixed with ethanol to make it spurious is (a) Methanol. Methanoic Acid (c) Methanal. (d) Ethanoic Acid. The metal oxide which can react with acid as well as alkali is (a) Silver oxide. Copper (II) oxide. (c) Aluminium oxide. (d) Calcium oxide. Carbon dioxide and sulphur dioxide gas can be distinguished by using (a) Moist blue litmus paper Lime water (c) Acidified potassium dichromate paper (d) None of the above. Organic compound obtained as the end product of the fermentation of sugar. (a) Methanol Ethanol (c) Ethane (d) Methanoic acid During ionization metals lose electrons this change can be called (a) Oxidation Reduction (c) Redox (d) displacement Ammonia is soluble in water because it is (a) An acid A base (c) A polar molecule (d) A simple covalent molecule Hydrogen chloride gas being highly soluble in water is dried by (a) Anhydrous Calcium chloride Phosphorous pentoxide (c) Quick lime (d) Concentrated Sulphuric acid. Which of the following properties do not match with elements of the halogen family (a) They have seven electrons in their valence shell. They are highly reactive chemically. (c) They are metallic in nature. (d) They are diatomic in their molecular form. [10] 277

2 X - ICSE (Chemistry) MT EDUCARE LTD. (x) Which of the following combination is true for carrying out electroplating of an (a) Direct and large current. Alternating and large current. (c) Alternating and small current. (d) Direct and small current. (c) A hydrocarbon P contains 14.3% hydrogen. Calculate its empirical formula. The relative molecular mass of it is 28. Calculate its molecular formula. Name the organic compound P. Write the structural formula of P. (d) Six elements A, B, C, D, E and F have the following atomic number A = 12, B = 17, C = 18, D = 7, E = 9, F = 11 Answer the following : Which one of them has the lowest electron affinity? Which one of them has the largest atomic size? Which of them belongs to the third period and has the highest ionization energy? Arrange the elements of the same group in increasing order of ionization potential. Write the chemical formula of the compound formed between F and B. (e) State your observation for the following : Conc. Sulphuric acid is added to sugar. Nitric oxide is passed through freshly prepared Ferrous sulphate solution. Sodium hydroxide is added to lead nitrate solution first a little then in excess. Ammonium hydroxide is added to sulphate solution first a little and then in excess. Concentrated nitric acid is added to copper. (f) What percentage of water is found in Na 2 S.9H 2 O? [Na = 23, S = 32, H = 1, O = 16] (g) (h) Form the list of substances, choose one substance in each case which matches the descriptions to given below : [ethene, hydrogen chloride, ethyne, ammonium chloride, nitric oxide, ammonium nitrate] The oxidized product of catalytic oxidation of ammonia. A nitrate which produces nitrous oxide on heating. A covalent compound which produces ions when dissolved in water A salt made of a non metal and used in dry cells. An unsaturated hydrocarbon with double bond between carbon atoms. Give IUPAC names of the following compounds. H 2 C = C CH 3 CH 3 CH 3 CH 3 SECTION - II (Attempt any four questions) Question 2. (a) Select the correct answer from the list in bracket : A covalent compound which in aqueous state conducts electricity. (CuCl 2, CS 2, NH 3,C 2 H 4 ) 278

3 MT EDUCARE LTD. X - ICSE (Chemistry) The cation discharged at the most readily. (Fe 2+, Cu 2+, Pb 2+, H 1+ ) 2- The anion discharged at at the anode with most difficulty (SO 4, Br -, NO -, OH - ) The metallic electrode which does not take part in an electrolytic reaction (Pt, Ag, Fe, Ni) The ion/s which is/are discharged during electrolysis of aqueous PbBr 2 solution using an electrode. (Pb 2+, Br 1-, H +, OH - ) (c) State the reaction occurring At the anode during the electrolysis of copper sulphate solution using a platinum anode. At the cathode during the electroplating of a key with nickel. At the cathode during the electrometallurgy of potassium. Give balanced equation for the following conversions. Bromoethane A Ethane B Sodium propionate Question 3. (a) The equations given below relate to the manufacture of sodium carbonate (Molecular weight of Na 2 CO 3 =106) NaCl + NH 3 + CO 2 + H 2 O NaHCO 3 + NH 4 Cl 2NaHCO 3 Na 2 CO 3 + CO 2 + H 2 O The following question is based on the production of 21.2g of sodium carbonate. What mass of sodium hydrogen carbonate must be heated to give 21.2g of sodium carbonate (Molecular weight of NaHCO 3 = 84) To produce the mass of sodium hydrogen carbonate calculated in the above question i, what volume of carbon dioxide, measured at S.T.P would be required? Hydrogen chloride dissolves in water forming an acidic solution. Name the experiment which demonstrates that hydrogen chloride is highly soluble in water. Explain : dil. HCl cannot be concentrated by distillation. Name the gas evolved when dilute hydrochloric acid is added to Manganese (IV) oxide. (c) Name the following : A nitrate which forms a yellow fused solid on heating. A nitrate which dissociates to give laughing gas. Question 4. (a) In the laboratory or industrial, the first step in the conversion of sulphur to sulphuric acid is to produce sulphur dioxide. Then sulphur dioxide converted to sulphur trioxide which reacts with water producing sulphuric acid. Name one catalyst used industrially which speeds up the conversion of sulphur dioxide to sulphur trioxide. Write the equation for the conversion of sulphur dioxide to sulphur trioxide. Why does the equation supply energy. What is the name of the compound formed between sulphur trioxide and sulphuric acid? Write a balanced chemical equation to show the action of conc. Sulphuric acid on glucose. 279

4 X - ICSE (Chemistry) MT EDUCARE LTD. With reference to the first three periods of the modern periodic table, answer the questions given below. Write the formula of the sulphate of the element with atomic number 13. Name the alkali in the third period. What is the name given to the energy released when an atom in its isolated gaseous state accepts an electron to form an anion. What type of bonding will be present in the oxide of the element with atomic number 1? State whether ionization potential increases or decreases on going down a group? Question 5. (a) Give chemical equation for the following : The laboratory preparation of methane from sodium acetate. The reaction of one mole of ethene with one mole of chlorine gas. The oxidation of methane in the presence of potassium dichromate. Neutralization of acetic acid by alkali. Formation of ester from acetic acid and ethanol. Al is extracted from its ore, Bauxite. The ore is first purified. Write 3 balanced equations for the purification of bauxite by Baeyer s process. Name a chemical used for dissolving aluminium oxide. Write an equation for the reaction which takes place at the anode during the extraction of Al by electrolytic process. Question 6. (a) Solution A has a ph of 12, solution B has ph of 5 and solution C has ph of 3. Which solution Will liberate ammonia from ammonium sulphate on heating? Is a strong acid? Contains molecules as well as ions? The following table shows the tests of students performed on four aqueous solution A, B, C and D. Write down in your answer scripts the observations to that were made. Test To solution A, barium chloride solution and hydrochloride acid were added. To solution B, sodium hydroxide solution was added. To solution C, ammonium hydroxide was added slowly till in excess To solution D, ammonium hydroxide was added slowly till in excess Observation (c) Fill in the blanks with the correct words from the brackets : An alloy which is sonorous is [duralumin/ bell metal/ type metal] The non metallic component in stainless steel is [sulphur / phosphorous/ carbon] The metal other than aluminium present in both magnalium and duralumin is [magnanese / magnesium / copper] Conclusion A contains 2 SO 4 B contains Fe 3+ C contains Zn 2+ D contains Mg 2+ [4] 280

5 MT EDUCARE LTD. Question 7. (a) Ca(OH) 2 + 2NH 4 Cl CaCl 2 + 2NH 3 + 2H 2 O 37g of Ca(OH) 2 reacts completely. Calculate : X - ICSE (Chemistry) Number of moles in 37g of Ca(OH) 2 Number of moles of NH 4 Cl required. Weight of NH 4 Cl required. (Ca = 40, N = 14, H = 1, O = 16) Draw the structural formula of a compound with two carbon atoms in each of the following cases : An alkane with a carbon-carbon single bond. An alcohol containing two carbon atoms. An unsaturated hydrocarbon with a carbon - carbon triple bond. (c) Match the following : Column A Column B 1. Acidic salt A. sodium potassium carbonate 2. Mixed salt B. Alum 3. Complex salt C. sodium carbonate 4. Double salt D. Sodium zincate E. sodium hydrogen carbonae. [4] 281