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THE BEST ACADEMY, UDYAVRA, CBSE 15T TERM TEST -2021, , SUB: SCIENCE DURATION: 45 mins, TOPIC: CH 1: CHEMICAL REACTIONS (MCQ) Total marks: 40, , 1. Which gas is filled in chips packet, , a) Hydrogen b) carbon dioxide c) Nitrogen d) Oxygen, 2. What happens when dilute hydrochloric acid is added to iron fillings, , a) Hydrogen gas and iron chloride are produced, , b) Chlorine gas and iron hydroxide are produced, , c) No reaction take place, , d) Iron salt and water are produced., 3. Burning of coal is an, , a) Exothermic reaction c) Combination reaction, b) Oxidation reaction d) all the above, 4. We store silver chloride in dark coloured bottles because itis, a) Awhite solid c) to avoid decomposition by sunlight, b) Undergoes redox reaction d) None of the above, 5. What is the change in the colour of the following reaction: Fe + CuSO, > FeSO, + Cu, a) Red to yellow c) Blue to green, b) Green to blue d) Yellow to white, 6. In which of the following heat energy will be evolved, a) Electrolysis of water c) burning of L.P.G, , b) Dissolution of ammonium chloride —_d) Decomposition of silver bromide, 7. For decomposition reaction energy is required in the form of, , a) Heat b) electricity c) Light d) All the above, 8. On passing gas, lime water turns milky. The passing gas is, a) Argon b) Carbon dioxide —_c) carbon monoxide d) hydrogen, 9, Chemical formula of rust is, a) Fe203 b) FeCO3 ¢) Fe203. xH20 d) FeCO3 xH20, 10. Rancidity occurs when oils and fats are, a) Reduced b) oxidized c) decomposed d) None of the above, 11. For rusting of iron the essential requirement is, a) Air b) water ¢) open surface of the metal d) all the above, , 12. Reaction involved in respiration, a) 6COz + 6H20 + —suolight —»C,Hi20¢ + 602, Chloraphyit, b) CeHi205+02 > 6CO2 + 6H20 + Energy, c) C+02. — COz, d) 4€0+0 — 4C02, 13. Formula of Slaked Lime, a) CaO b) Ca(OH)2 c) CaOH d) CaO2H, 14. Which of the following is a balanced equation?, a) Fe+ 4H2,0 — Fe3Qs + 4Hz, b) 3Fe+4H20 — Fe3Q4 + 4H2, c) 3Fe+H20 — Fe304+ H2, d) 3Fe+4H20 — FesOs+ He

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15. In the below given reaction which substance is oxidized: CuSO, + Fe — Cu+ FeSO,, a) Fe b) FeSO, c) CuSO, d) Cu, 16. Why is it important to balance skeletal equation?, a) To verify law of conservation of energy, b) To verify law of constant proportion, c) To verify the law of conservation of mass, d) To verify law of conservation of momentum, 17. A gas evolved when acid reacts with metal is, a) Nitrogen b) Hydrogen c) Oxygen d) Carbon Dioxide, 18.Pb(NOs)2+2KI — Pbly + 2KNO; Which of the following changes taken place in the given, reaction?, , , , a) Colour Change c) Formation of Precipitation, b) Temperature Change d) Pressure Change, 19. 2FeSO, =F e203 +_X__ + __Y., a)X=SO, Y=CO,, b) X= SOs Y =SOz, c) X= SO; Y=co, d) X= S02 Yy=co, 20. What may happen during a chemical reaction?, a) Change in state c) Change in temperature, b) Change in colour d) All of the above, 21. Which reaction will be take place in the presence of sunlight, a)2H:0 + 2H, +02 c) 2AgBr > 2Ag + Br2, b) CaCOs > CaO + COz d) NaOH + HCl > NaCl +H20, , 22. Which reaction is example for double displacement reaction, a) AgNO; +NaCl — AgCl + NaNO;, b) CaO + H20 — Ca(OH)2, ¢) KCIO3 — 2KCl+ 302, d)Zn+CuSO4 — ZnSO« + Cu, 23. What do you mean by exothermic reaction?, a) Reaction in which heat is absorbed, b) Reaction in which heat is evolved, ¢) Reaction in which no change in heat, d) Reaction in which pressure increased, 24. Give the ratio in which hydrogen and oxygen are present in water by volume., , (a) 1:2 (b) 1:1 (c) 2:1 (d) 1:8, 25. When Ag is exposed to air it gets a black coating of, (a) AgNO; (b) AgeS (c) Ag20 (d) Ag2COs, , 26. Which among the following statement(s) is (are) true?, Exposure of silver chloride to sunlight for a long duration turns grey due to, i) The formation of silver by decomposition of silver chloride, ii) Sublimation of silver chloride, iii) Decomposition of chlorine gas from silver chloride, iv)Oxidation of silver chloride, , {a) (i) only (b) (i) and (iii) (c) (ii) and (iii) (d) (iv) only, 27.A substance ‘X’ is used in white-washing and is obtained by heating limestone in the absenceof, air. Identify ‘x’., , (a) Ca0Cly (b) Ca(OH). (c) CaO (d) CaCO;

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28.A substance added to food containing fats and oils is called:, (a) Oxidant (b) Rancid (c) Coolant (d) Antioxidant, , 29. Pb + CuCl, ~ PbClz + Cu. The above reaction is an example of:, (a) Combination (b) displacement c)decomposition d) double displacement, 30. Which of the following gases can be used for storage, , (a) Carbon dioxide or Oxygen (b) Nitrogen or Oxygen, (c) Carbon dioxide or Helium (d) Helium or Nitrogen, 31. The colour of precipitate formed when barium chloride solution is mixed with soldium, sulphatesolution is, a) blue b) black c) white d) green, , 32. Which of the following statements about the — given reaction are, correct? 3Fe (s) + 4H20 (g) Fe3Os (s) + 4 H2 (g), (i) Iron metal is getting oxidised, (i) Water is getting reduced, (iii) Water is acting as reducing agent, (iv) Water is acting as oxidising agent, (a) (i), (ii) and (iii) (b) (iii) and (iv) (c) (i), (ii) and (iv) (d) (ii) and (iv), 33. Oxidation is a process which involves, , (a) Addition of oxygen (b) addition of hydrogen, (c) Removal of oxygen (d) addition of electron, 34. FeO + 2Al 3+ 2Fe, (a) AlO3 (b) ALO (c) (Al0)2 (d) AlLOs, , 35. Three beakers labelled as A, B and C each containing 25 ml of water were taken. A small, amount of NaOH, anhydrous CuSO, and NaCl were added to the beakers A, B and C respectively., It was observed that there was an increase in the temperature of the solution contained in, beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one, of the following statement(s) is (are) correct?, (i) In beakers A and B, exothermic process has occurred., (ii)In beakers A and B, endothermic process has occurred., (iii) In beaker C exothermic process has occurred., (iv) In beaker C endothermic process has occurred., (a) (i) only (b) (ii) only (c) (i) and (iv) (d) (iv), (ii) and (iii), 36. Flectrolysis of water (i.e.2Hz0 — 2H +02) isan examples for__, a) Combination reaction, b) Precipitation reaction, c) Decomposition reaction, d) Displacement reaction, 37. Which of the following are exothermic processes?, (v)Reaction of water with quick lime, (vi) Dilution of an acid, (vii) Evaporation of water, (viii) Sublimation of camphor (crystals), (a) (i) and (ii) (b) (ii) and (iii) (c) (i) and (iv) (d) (ii) and (iv), 38, Name the products formed when iron filings are heated with dilute hydrochloric acid, , (a) Fe (IIT) chloride and water (b) Fe (ID) chloride and water, (c) Fe (11) chloride and hydrogen gas (d) Fe (III) chloride and hydrogen gas, , 39. When crystals of lead nitrate are heated strongly in a dry test tube, a) Crystals immediately melt b) a brown residue is left, c) White fumes appear in the tube d) a yellow residue is left

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40. On immersing iron nail in CuSOs solution for few minutes, you will observe that, a) No reaction takes place, b) The colour of solution fades away, c) The colour of solution changes to green, d) The surface of iron nails acquire a black coating