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/ I IDRANANDANI FOUNDATION SCHOOL, THANE First Preliminary Assessment, November 2024 I Subject: Chemistry CLASS: X DATE: Time: Two hours 1..4/ II /1oi4 Max Marks: 80 Answers ~o this paper must be written on the separate answer sheet. The time given at the head ofthis paper is the time allotted to write the answers. This question paper consists of07 printed pages. The time given at the head ofthis paper is the time allowedfor writing the answers. ' Section A is compulsory. Attempt any four questions from Sectio~ B. The intended marks for each question or sub-question are given in the brackets { ]. M , 1 SECTION A (Attempt all questions from this Section) Question 1 Choose one correct answer from the given options: (Do not copy the question, write the correct answer only.) ' i) When a compound was electrolysed using inert electrodes, the gas released at the anode made a glowing splinter rekindle. The electrolyte that will not produce such gas at the.anode is: a) diluted solution of NaCl. b) concentrated solution of NaCl. c) diluted solution of copper sulphate. d) acidified water. ii) The white precipitate which is soluble in excess ofNH,OH is of _ _ _ __ a) Lead chloride b) Barium chloride c) Silver chloride d) Zinc chloride iii) The molecular masses ,ofhydrogen, Sulphur dioxide and chlorine are 2, 64 and 71 respectively. Statement A: 2g of hydrogen contains same number of molecules as 71 g of Chlorine. Statement B : 2 g of hydrogen contains same number of molecules as 32 g of Sulphur dioxide. a) Only A is correct b) Only B is correct c) Both A and B are correct d) Neither A nor B is correct iv) Assertion (A) : Pb(OH)CI is a basic salt. Reason ( R): The OH 1 ions of Pb(OH)2 are partially replaced by H1+ions of acid. Page 1 of 7 [15] I I a) Both (A) and ( R) 8fC tru~ and ( R) is the correct expJanation ?~ (A) b) Both (A) and ( R) true' but ( R) is not the correct exp~anation of (A). are c) (A) is true but ( R) is false. d) (A) is false but ( R) is true. v) In Haber's process, ammonia is separated and recover~d from uncombined_nitro:~. a~d , hydrogen. These techniques of separation are based on which of the followmg P ysrc properties of ammonia? / Property I: Ammonia is highly soluble in water. Property II: Ammonia is lighter than air. Property m: Ammonia is a basic gas. Property IV: Ammonia is easily liquefiable. a) I and II b) II and 1n c) III and IV d) I and IV vi) An element in period 3, whose electron affinity is zero. a) Neon b) Sulphur c) Argon d) Sodium vii) A compound A3B2 has the following ions: a) A2+, B3+ b) B2+, A3 c) A3+, B2_. / d) A2+, B3 viii) Assertion (A): Al3+, Na+, 02 , c1 1 are examples of ions. Reason (R) : All these ions have 10 electrons. a) Both (A) and ( R) are_ true and ( R) is the correct explanation of ( A) b) Both (A) and ( R) are true , but ( R) is not the correct explanation of (A). c) (A) is true but( R) is false. d) (A) is false but ( R) is true. ix) The metal oxide which can react with acid as well as alkali is - ._a) Silver oxide b) Copper (II) oxide c) Aluminium oxide d) Calcium oxide x) The catalyst used in Contact process is: a) Nickel b) Finely divided Iron c) Vanadium pentoxide d) Platinum xi) Given below are four covalent molecules. (A) H2O, (B) CCL., (C) Ch, (D) Nl-h Which of the following represents the correct order when they are arranged in their increasing number of lone pairs of electrons?. a) b) c) d) B<D<C<A A<C<D<B D<A<C<B C<A<D<B 'J Page 2 of 7 "'ii xii) The hydrolytic method for the concentration of the ore is based on the principle of difference in -------- a) magnetic nature. b) density. c) hydrophobic nature. d) solubility. xiii) The mass of 14.5 litres of ammonia gas at s.t.p. is _ _ _. [Atomic weights are N=l4, Hydrogen =l] a) 11 g b) 1.10 g c) 17 g d) 26.4 g -xiv) The statements below show the results when three metal strips, P, Q, and R, are placed in blue copper sulphate solution. P- Solution turns green. Q- Solution becomes colourless. R- Solution remains blue. Which of the following metals could be P, Q, and R? a) P-Al, Q-Zn, R- Fe b) P-Zn, Q-Fe, R- Ag c) P-Fe, Q-Zn, R-Ag d) P- Zn, Q-AI, R- Fe xv) Solder is an alloy of_ _ _ __ a) Cu+Sn b) Cu+Zn c) Pb+ Sn d) Cu+ Pb Question 2 i) With respect to laboratory preparation of an alkaline gas, answer the questions that follow the diagram given below: Mixture X a) b) c) d) e) Write the balanced e?,uation for the preparation of gas shown above. Name the substance Y' and state its use. Sta~ the obse"'.ation when the gas prepared is burnt with excess of oxygen. Which method 1s used to collect this gas How will you confirm that the gas jar is full of the alkaline gas? Page 3 of 7 ..... .. ,.. --."fr~~~ - [5] ii) Match the following column 'A' with column 'B'_ (Use ea~h ~ption only a) Funnel arrangement 1. Nitroso iron[II]sulphate b) Calamine 2. Hydrochloric acid c) Brown ring test 3. Liquor ammonia d) Non-volatile acid 4. Zinc carbonate 5. Sulphuric acid 6. Liquid ammonia iii) Cleansing agent [5] ColumnB Column A e) once) Complete the following by choosing the correct answer from the bracket. [5] a) If an clement has seven valence electrons, it is likely to have the _ _ _ [largest/smallest] atomic size among all the elements of the same period. b) The polar covalent compound that does not conduct electricity in the gaseous state is _ _ _ _ _ _ _ [Methane/Ammonia]. c) The _ _ _ [higher/lower] the concentration of an ion in a solution , the greater is the probability of it being discharged at respective electrode. d) When ammonia [in excess] is mixed with chlorine, chlorine is _ _ _ _ [oxidized to HCI/ reduced to HCl] e) _ _ [AhOJ/ Fe2O3] is the chemical formula of corundum. iv) Identify the following: [5] a) Name the process by which nitric acid is manufactured in the industry. b) A type of bond formed between atoms of non-metallic elements having large difference in their electronegativities. c) State the formula of the salt formed when impure Bauxite is heated with cone. NaOH under pressure. d) Identify the type of particles present in a liquid such as kerosene which is a nonelectrolyte. e) The amount of energy released when an atom in the gaseous state accepts an electron to form an anion. v) a) Identify the gas evolved in each of the following reactions. 1. Copper reacts .with cold, dilute nitric acid. 2. Manganese dioxide is heated with cone. Hydrochloric acid. 3. Gas liberated at anode on electrolysis of acidified water. b) Ammonia dissolves in water and forms a positive ion and a negative ion. Draw the electron dot structure of the fonnation of positive ion. [3] [2] Section B (Attempt any four questions) Question 3 i) Identify the reactant and write the balanced equation for the following: (2] A black coloured compound 'X' reacts with cone. HCl to give blue colour solution. ii) 1 litre of Hydrogen gas weighs 0.09 g at s.t.p. If the weight of 1OO0mL of a gas 'X' at s.t.p. is 3.15 g, find Molecular weight of"X". Page 4 of 7 [2) Write the products and balance the equations: a) Ca3N2 + H20 -+ b) Cu(N03)2 [3] /J. c) KHC03 + H2SO4 (dil.)-+ iv) The atomic numbers of element X, Y and Z are 71 3 and 10 respectively. With reference to this, answer the following questions: Which of these elements combines with Hydrogen gas to fonn a basic gas? a) Which amongst these elements will have highest Ioniz.ation potential? b) Which of these elements fonns ionic compound with Chlorine? c) j [3] ' Question 4 s X and Y. i) The equations given below represents the molecule formation of element Draw the electron dot structures of the molecules (a) and (b). 1) . X., + , ,.) ~1= ii) iii) + [2] Eo.~ . x .,, . Determine the empirical formula of compound having vapour density as 45 and the following percentage composition: C=26.59%, H= 2.22% and O= 71.19%. [At.Wt. C=12, H=l and 0=16]. ,. [2] and The following sketch illustrates the Hall Heroult's process. Study the sketch [3] answer the foJlowing questions. __, -44------ y..___..,._..,.....,.-r--T....., Electrolyte __.. .,.:. Mixture z a) Why is it necessary for the electrode 'Y' to b~ continuously replaced? b) Write the reaction taking place at electrode 'Z'. c) Write the molecular formulae of all the constituents of electrolytic mixture. Page 5 of 7 I I I . . l~ J iv) The reactants for preparation of different salts nre _give~ in cotufun A. Match each of them with the method of preparation for salts given irt colomn B. [3] ColumnB Column A a) b) c) Lead (Il)hydroxide, dil. Nitric acid Magnesium, dil. Hydrochloric acid Calcium chloride, Sodium carbonate 1 precipitation 2 direct combination 3 displacement 4 neutralization - Question S i) Write the name of the alloy based on the given composition: a) Al+Mg+Mn+Cu b) Cu+Zn+Sn ii) Atomic mas, of Sulphur= 32 and of Oxygen =16. If Avogadro's number= 6xl023, calculate: a) Volume of320 g ofSO2 b) Mass of 1022 atoms of Sulphur. [2] [2] iii) Write the balanced chemical equations for each of the following: a) Reaction at cathode during electrolysis of molten Lead bromide. b) Addition of ammonia solution to a Copper sulphate solution forming a pale blue precipitate. c) Preparation of a non-volatile acid using a volatile acide and a non-metal. iv) Sbrecya was analysing a salt 'X' in the laboratory. On action of heat on this salt, a pungent smelling gas was evolved which gave dense white fumes with glass rod dipped in the cone. HCI. On addition of BaCh solution to the aqueous solution of salt 'X', a white precipitate (insoluble in dil.HCl) was formed. (3] a) Identify the cation and the anion present in the salt 'X'. b) Name the anion which gives the white precipitate with BaCh solution but is soluble in dil.HCl? [3] Question 6 i) In preparation of Hydrochloric acid, special funnel arrangement is used for the absorption ofHCl in water. State two advantages of this arrangement. [2] ii) A gas 'P' occupies a volume of 1.2 litres and contains X molecules. Under similar conditions of temperature and pressure, how many molecules will be present in gas 'Q' occupying a volume of 400 c.c? Which law forms the basis of the above calculation? [2] iii) Abhishek wants to electroplate article with Nickle. a) Which solution should he take as an electrolyte? b) To which electrode should he connect the article to be electroplated? c) Why should he use a low current for a longer duration for this process? iv) Lithium, Sodium and Potassium are placed in one group of the modem periodic table. i) Why do these elements show similar properties? ii) What is the common name of this group of elements? iii) Why are these elements known as strong reducing agents? Page 6 of 7 [3] [3] ,, ,, . Question 7 i) . . Write the balanced chem 1caI equati on for each of the following conversions: r:- , a)_ r:-::-7 (b) r:: :-7 i) (c) .... [ Fe(OH)2 ii) J [3] : Write the chemical fonnula of the following compounds a) Olewn b) Iron pyrite c) Sodiwn argentocyanide [3] ' ding to the [4] 14, 1 ~:. ,) horic acid accor Concentrated nitric acid oxidises phosphorus to phosp wt Following equation: P + 5HNOJ --+ ff3PO.c + 5NO2 + H2O 3.1 g of phosphorus? a) What mass of phosphoric acid can be prepared from time? same the at med consu be will b) What mass of nitric acid t l-: 11, o::.I 61 ' Question 8 i) ii) iii) iv) the help of one chemical test. Distinguish between the following compounds with [2] (balanced equations are not required). a) Dilute sulphuric acid and dilute Hydrochloric acid (using Lead (Il)nitrate solution) cone. alkali) . b) Sodium sulphate and ammonium sulphate (using the pH of the solution Seema prepared solution 'X' with pH= 10. How will [2] ing? follow the of Change on addition a) Vinegar b) Potassium hydroxide [3] State giving reasons if: a) Acetic acid can fonn an acid salt. Hydrogen chloride gas. b) Quicklime can be used as a drying agent for acid for its dilution. uric sulph d ntrate conce to added be can r c) Wate (3] Write a suitable word or a phrase for the following: place. taJces tion a) An electrode at which oxida acid on its reaction with b) The property depicted by concentrated sulphuric mass. glucose to produce a black fluffy with a buff yellow compound c) The property depicted by ammonia when it reacts to greyish metal. Page 7 of 7 ,. ...... -......;,:.- .. ~- . . , .,- . .-
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