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HIRANANDANI FOUNDATION SCHOOL, THANE Second Preliminary Assessment, January 2023 Subject: Chemistry CLASS:X DATE:5/1/23 Time: 2 hours Max Marks: 80 sheet. Answers to this paper must be written on the separate answerthe answers. write to allotted time the The time given at the head of this paper is You will not be allowed to write during the first 15 minutes. This time is tobe spent in reading the question paper. This question paper consists of 06 printed pages. any four questions from Section B. Section A is compulsory. Atempt sub-question are given in the brackets J. or question each for The intended marks SECTION A (Atempt all questions from this Section) Question 1 Choose one correct answer to the questions from the given options: [15] the following takes place? i) During the electrolysis of acidified water, which of a) b) c) d) Oxygen is released at cathode Oxygen is released at anode Hydrogen is released at anode Sulphur dioxide is released at anode concentrated alkali gives salt and ii) Identify the hydroxide which on heating with a) Iron (III) hydroxide water. b) Calcium hydroxide c) Lead (U) hydroxide d) Potassium hydroxide 17,12 and 13 respectively. ii) The elements A, B, C, D and E have the atomic numbers 9,11, table is periodic the of group same to the belongs which The pair of elements t t s a) A and B b) Band D c) A and C d) D and E iv) Atomic masses of Silicon, Nitrogen and Hydrogen are 28,14 and 2 respectively. Which of the following statements regarding the number of atoms in 28g Silicon, 14g of Nitrogen and 2g of Hydrogen is correct? P: 14g of Nitrogen contains seven times the number of atomns as 2g of Hydrogen. Q: 14g of Nitrogen contains half the number of atoms as 28g of Silicon. a) Only P b) Only Q Both P and ) d) Neither P nor Q v) Ifthe PH of a solution is 2 then the solution is a) Strong acid b) Strong alkali c) Weak acid d) Weak alkali vi) The catalyst used in contact process is a) Platinum b) Finely divided Iron c) Vanadium pentoxide d) Graphite Page 1 of 6 Iron nail vii) Which apparatus is used to electroplate an with copper? 1RON NAIL w E X Aqueous copzT() suiphatt sCopper () sulphate Aqueous iron (U} sulplhate Aqueous iron () sulphate a) Option W b) Option X c) Option Y d) Option Z chemically with the viii) An element with atomic number 19 will most likely combine element whose atomic number is a) 20 b) 9 c) 11 d) 18 cutting metals. ix) An organic compound which is used for welding and a) Ethene b) Acetylene c) Ethanol d) Both a) and b) of x) Formation of chloro form from methane and chlorine is an example reaction. a) addition b) dehydration c) substitution d) dehydrohalogenation xi) The drying agent used to dry Ammonia gas prepared in the laboratory. a) b) c) d) P;0s Conc. HzSO4 CaClz CaO xii) Which of the following compounds neither dissociate nor ionise in water? a) Hydrochloric acid b) Sodium hydroxide c) Potassium nitrate d) Catbon tetrachloride Page 2 of 6 xii) Which of the following is acommon characterlatic of a High mclting covalent compound? point Conducts in its c) units are molten state Constituentclectricity a) b) d) Soluble in water molecules Xiv) The organic compound mixed with a) Methanal b) Methanol c) Acetic acid cthanol to make it spurious is d) acctylene xv) Which mctal cannot be used for clectroplating by using its aqueous a) nickel b) chromium c) sodium solution? d) gold Question 2 i) The set up shown below illustrates the apparatus used in the laboratory preparation of nitric acid. Observe the set up and answer the following qucstions: Cold wator a) Identify the reactants 'A' (a liquid) and 'B' (a solid) taken in a glass retort. b) Explain why an all-glass apparatus is used in the above preparation. c) Explain why is the molar ratio of reactants 'A' and 'B' is taken as 1:1. d) Although pure nitric acid is colourless, the acid collected in the flask 'C is slightly yellowish brown. Explain. Write the balanced chemical equation stating the conditions, for the reaction between 'A' and 'B'. Match the following column 'A' with column 'B.(Use cach option only once). i) Column B Column A 1 Converting ore into the fine powder b) Pulvcrization 2 Covalent compound c) Decarboxylation 3 Separation of ore and gangue a) Magnesium chloride 4 Elimination of a molecule of CO, from carboxylic acid. Methane e) iii Bayer's process Electrovalent compound 5. Complete the following by choosing the correct option from the bracket. a) An alkaline earth metal having lowest metallic character is (Lithium/ Beryllium] b) is an example of acid salt. [ CH;COONa/ Na)HPO] c) The salt solution which docs not react with Ammonium hydroxide is (Zinc nitrate/ Calcium nitrate] Page 3 of6 with reaction of ethylene by the.[1,2formed dichloroethane/ 1,2 product name of the d) The I.U.P.A.C. inert solvent is Chlorine, using an acid. dichloroethene] when added to nitric change colour a will not show e) [Phenolphthalein/Blue litmus solution) State the following: iv) a) A two bonded pairs covalent molecule containing and two lone pairs of sodium Iron (1) sulphate with by formed precipitate b) The colour of the same molecular hydroxide. organiccompounds having the which in phenomenon formula. c) The arrangement or in structural formula differ in molecular (2,8,4) in the configuration having electronic 'X element an of position d) The electrons. periodic table. alumina. elevated temperature gives pure e) The compound which at an compounds. of each of the following a) Draw the structural formula 1. propanoic acid v) (3] 2. methanol 3. 2-methyl but-1-ene b) Write the IUPAC name of the [21 following organic compounds. 1 H c c H 2 CH3 H Section B (Atempt any fourquestions) Question3 i) extraction ofAluminium from Answer the following questions with reference to the [3) pure Alumina by Hall- Heroult process. a) What is the function of Cryolite which is added to the electrolytic mixture? b) Give reason: A layer of powdered coke is sprinkled over the electrolytic mixture. c) Name the electrode from which Aluminium is collected. ii) Give balanced equations for each of the following reactions. a) Ammonia is bumt in the presence of a catalyst. b) Preparation of Hydrogen chloride gas in laboratory. iii iv) [31 c) Preparation of ethane using ethyl bromide. Calculate the percentage of Fluorine in Sodium aluminium fluoride. [atonic masses [2 are: Na=23,Al-;, F=19]) Copy and complete the following table which refers to the laboratory method of preparation of Ethene. [2) Name of the conpound Type of chemical Balanced equation reaction (state conditions) Ethene Page 4 of 6 Question 4 An atom P has atomic 7. electron in its K-shell. number It combines with an atom'Q' having one a) Write the formula of the compound formed between 'P' and b) Draw the electron dot structure of the [3] "Q. molecule forned between 'P" and 'Q. C) State the electrical of the compound formed between "P" conductivity and Q in its gaseous state. State whether the following statements are true or false. Justify your answer. (3] a) In the periodic table Caesium has the highest ionization potential. b) In methane molecule Carbon and Hydrogen atoms are bonded with a polar covalent bond. c) The volume occupied by 7g. Nitrogen at s.t.p. is 5.6. [Atomic mass of Nitrogen is 14]) iii) Draw the electron dot structure of the following: a) A stable positive ion formed when acid dissolves in water. [21 b) Ethane molecule iv) Identify the acid in each case: a) The acid which is used for the preparation of non-volatile acid. b) The acid which produces sugar charcoal from sugar. [21 Question 5 i State the property of Ammonia exhibited in the following reactions: (2] a) Ammonia reacts with Chlorine to form Hydrogen chloride. b) Liquid Ammonia is used as a refrigerant. Name the alloy for each of the given compositions: a) Copper and Zinc. b) Aluminium, Magnesium, Manganese, Copper. ii) iii) iv) [2] Identify the anion present in each of the following compounds. [3) a) Compound Xwhich on reacting with dil. H2S04 liberates a gas which turns lime water milky and acidified potassium dichromate from orange to clear green. b) Compound 'Y which on reacting with di.HCI, liberates a gas that turns moist Lead acetate paper silvery black. c) Compound 'Z' when heated with conc. H,SO4 and Copper turnings, gives a reddish brown gas. [3] Explain the following: a) Addition reactions are characteristic of alkenes while substitution reactions are characteristic of alkanes. b) During the electrolysis of aqueous CuSO4, the blue colour of aqueous copper [) sulphate solution remains unchanged when 'copper' electrodes are used but fades when 'platinum' electrodes are used. c) Hydrochloric acid is prepared by dissolving Hydrogen chloride gas in water using a special funnel arrangement and not by direct absorption of HCl gas in water. Question6 i [21 State the following: a) The process of heating the concentrated ore in presence of excess air to a high ii) temperature. b) Tendency of an element to form chains of identical atoms. Acylinder contains 68g of Ammonia at s.t.p. [Atomic mass: N=14, H=1] a) Calculate the volume occupied by the gas. b) Calculate the number of moles of Ammonia, present in the cylinder. Page 5 of 6 [2] iv) (3] State one observation for the following reactions: a) Sodium bydroxide is added dropwise to Lead (IInitrate solution. b) Zinc metal is treated with hot concentrated alkali. c) Copper (II) oxide is treated with excess of ammonia solution. Arrange the following as directed: (31 a) Si, P, Mg, Cl(decreasing order of electronegativity). b) Al, S, Na, Cl (increasing order of atomic size). c) CI, NO;, OH, SO (increasing ease of oxidation) Question 7 12.5% of Hydrogen by Agaseous compound of nitrogen and Hydrogen contains relative molecular mass is ii) mass. Find the molecular formula of the compound if its 32. [Atomic masses are N= 14, H=1] the From the list of substances given in the bracket, choose the reactants for (3) the preparation of the given salts a) to c) and write balanced chemical equation for dilute nitric acid, dilute same. [Lead(II) oxide, Iron, dil. Hydrochloric acid, Chlorine, 3] sulphuric acid, Calcium chloride, Sodium sulphate, Sodium carbonate] iii) a) Lead (II) nitrate b) Iron (I) chloride c) Calcium carbonate according to the a) Concentrated nitric acid oxidises phosphorus to phosphoric acid following chemical equation: P+ SHNO, H3PO4+ H;0+ 5NO 1) What mass of phosphoric acid can be prepared from 6.2g Phosphorus? 2) What mass of nitric acid will be consumed at the same time? measured 3) What would be the volume of steam produced at the same time and at s.t.p.? [Atomic masses: H=1, N= 14, 0= 16, P=31]. b) Define Vapour Density'. [4] Question 8 i) [2 Differentiate between the following: a) Alkanes and Alkenes (based on their general formula). b) Oxidising electrode and reducing electrode (based on the types of ions which get discharged at it). The elements Na, AL, Si, P, S, Cl and Ar belong to the same period of the periodic table. Answer the following questions based on this fact. (2] a) Identify the period of the periodic table to which these clements belong? b) ldentify the missing element of this period and write the formula of its sulphid. Write balanced chemical equation for each of the following reactions: a) Preparation of ethane from sodium propionate. b) Reaction of ethanol with acetic acid in presence of conc. Sulphuric acid. [3) c) Formation of ethane from ethene. jV) [3 Identify the following substances: a) Agas which turns acidified potassium permanganate solution from pink to clear colourless. b) The solution used in the test to distinguish dilute Sulphuric acid from dilute Hydrochloric and Nitric acid. c) An electrolyte used in electroplating of an article with Nickel. Page 6 of 6
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