CLASS 10 SCIENCE 1. CHEMICAL REACTION & EQUATIONS MULTIPLE CHOICE QUESTIONS

Multiple Choice Questions:

 

  1. 10g of hydrogen is burnt in the presence of excess oxygen. The mass of water formed is
    a) 90 g                                       b)   45 g                       c)   10 g                       d)   18 g

 

  1. Reddish – brown copper metal forms a black solid on combustion. Which of the following statement is incorrect?
    a) Black solid is CuO.                                                           b)  The reaction is a redox reaction.                                                                                  c) The reaction is precipitation reaction.                         d)  Copper is being oxidized.

 

  1. The electrolytic decomposition of water gives H2 and O2 in the ratio of
    a) 1 : 2 by volume                                        b) 2  : 1 by volume
    c) 8 : 1 by mass                                            d) 1 :  2 by mass

 

  1. Which of the following gases can be used for storage of fresh sample of oil for a long time?
    a) Carbon dioxide or Oxygen                                                  b) Nitrogen or Helium
    c) Helium or Oxygen                                                                d) Nitrogen or Oxygen

 

  1. Both CO2 and H2 gases are
    a) Heavier than air                                                                     b)  Colourless
    c) Acidic in nature                                                                      d)  Soluble in water

 

  1. Chemically rust is
    a) Hydrated ferrous oxide                                                        b) Only ferric oxide
    c) Hydrated ferric oxide                                                            d) None of these

 

  1. Which of the following reaction is used in the whitewashing of walls?
    a) 2Ca +  O2  → 2CAO                                                               b) CaO + H2O → Ca(OH)2 + ∆
    c) Ca(OH)2 + CO2  → CACO3 + H2O                                     d) Ca (OH)2 → CaO + H2O

 

  1. 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

 

  1. When carbon dioxide is passed through lime water,
    a) Calcium hydroxide is formed                                              b) White precipitate of CaO is formed
    c) Lime water turns milky                                                        d) Colour of lime water disappears

 

  1. On immersing an iron nail in CuSO4 solution for few minutes, you will observe
    a) No reaction takes place                                                        b) The colour of solution fades away
    c) The surface of iron nails acquire a black coating            d) The colour of solution changes to green

 

  1. The reaction in which two compounds exchange their ions to form two new compounds is called
    a) Displacement reaction                                                          b) Combination reaction
    c) Double displacement reaction                                            d) Redox reaction

 

  1. In the reaction CuO + H2 → Cu + H2O, the correct statement is
    a) CuO is an oxidising agent                                                    b) H2 is getting oxidised
    c) The reaction is a displacement reaction                           d) All of these

 

  1. Which of the following is not an example of a single displacement reaction?
    a) CuO + H2 → H2O + Cu                                                               b) Zn + CuSO4   → ZnSO4 + Cu
    c) 4NH3 + 5O2 → 4NO + 6H2O                                                     d) Zn + 2HCI  → H2 + ZnCl2

 

  1. Rancidity can be prevented by
    a) Adding antioxidants                                                                    b) Storing food away from light
    c) Keeping food in refrigerator                                                      d) All of these

 

  1. In which of the following , heat energy will be evolved?
    a) Electrolysis of water                                                                    b) Dissolution of NH4 Cl in water
    c) Burning of P.G.                                                                             d) Decomposition of AgBr in the pressure of sunlight

 

Answers:

1. a)                2. c)                 3. b)                 4. b)                 5. b)
6. c)                 7. c)                 8. b)                 9. c)                10. d)
7. c)               12. d)                13. c)               14. d)               15. c)

Previous Topic
Back to Lesson