Q1. Dilute hydrochloric acid is added to granulated zinc taken in a test tube.The following observations are recorded. Point out the correct observation.
(A) The surface of metal becomes shining
(B) The reaction mixture turns milky
(C) Odour of a pungent-smelling gas is recorded
(D) A colourless and odourless gas is evolved
Q2. 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.
Q3. When a magnesium ribbon is burnt in air, the ash formed is
(A) black
(B) white
(C) yellow
(D) pink
Q4. In which of the following, heat energy will be evolved?
(A) Burning of L.P.G.
(B) Dissolution of NH4Cl in water
(C) Electrolysis of water
(D) Decomposition of AgBr in the presence of sunlight
Q5. Rancidity can be prevented by
(A) adding antioxidants
(B) storing food away from light
(C) keeping food in refrigerator
(D) all of these
Q6. The reaction of H2 gas with oxygen gas to form water is an example of
(A) combination reaction
(B) redox reaction
(C) exothermic reaction
(D) all of these reactions
Q7. 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
Q8. On immersing an iron nail in CuSO4 solution for few minutes, you will observe
(A) no reaction takes place
(B) the colour of solution changes to green
(C) the surface of iron nails acquire a black coating
(D) the colour of solution fades away
Q9. An element X on exposure to moist air turns reddish-brown and a new compound Y is formed. The substance X and Y are
(A) X = Fe, Y = Fe2O3
(B) X = Ag, Y = Ag2S
(C) X = Cu, Y = CuO
(D) X = Al, Y = Al2O3
Q10. Which of the following is termed as oxidizing agent?
(A) Which gives oxygen
(B) Which removes oxygen
(C) Which gives hydrogen
(D) All of the above
Q11. Which of the following termed as reducing agent?
(A) Which gives oxygen
(B) Which removes oxygen
(C) Which removes hydrogen
(D) All of the above
Q12. Which of the following does show oxidation reaction?
(A) Gain of oxygen
(B) Loss of oxygen
(C) Gain of hydrogen
(D) None of the above
Q13. Which of the following does show reduction reaction?
(A) Gain of oxygen
(B) Loss of oxygen
(C) Loss of hydrogen
(D) None of the above
Q14. Which of the reaction is used in black and white photography?
(A) Combination reaction
(B) Decomposition reaction
(C) Displacement reaction
(D) Oxidation reaction
Q15. In which of the following heat is evolved?
(A) Combination reaction
(B) Decomposition reaction
(C) Displacement reaction
(D) Double displacement reaction
Answer:
1. (D)
2. (C)
3. (B)
4. (A)
5. (D)
6. (D)
7. (C)
8. (B)
9. (A)
10. (A)
11. (B)
12. (A)
13. (B)
14. (B)
15. (A)