Changes around us Worksheet-5

Changes around us Worksheet-5

 

Fill in the blanks:

  1. Melting of chocolate is:

(A) A chemical change                    (B) None of these

(C) A physical change

 

  1. Ripping of paper is a:

(A) A chemical change                    (B) A physical change

(C) None of these

 

  1. Burning of firecracker is:

(A) Chemical and irreversible change

(B) Physical and reversible change

(C) Physical and irreversible change

(D) Chemical and reversible change

 

  1. Heating causes _________ in a material.

(A) relaxation      (B) contraction    (C) expansion

 

  1. _________ causes contraction in a material.

(A) Heating          (B) Cooling          (C) Melting

 

  1. Paint dries on the walls after a few hours.

(A) It is a physical and irreversible change

(B) It is a chemical and reversible change

(C) It is a physical and reversible change

(D) It is a chemical and irreversible change

 

  1. When we spray perfume on our body, we feel cold. Why?

(A) It is because the spray droplets have lower temperature than our body.

(B) It is because the spray droplets have higher temperature than our body.

(C) It is because the spray droplets contain water.

(D) None of these

 

  1. Sometimes it rains for a short time in the morning, but by the afternoon the puddles disappear. Why?

(A) None of these

(B) It disappears due to evaporation

(C) It disappears due to condensation

 

  1. Clothes dry on a clothesline on a sunny day. It is due to:

(A) Heating                                       (B) Condensation

(C) Evaporation                               (D) None of these

 

  1. Vegetables lie on a rack in the steamer. But as the steam rises around them, the water droplets accumulate on the lid. Why?

(A) It happens due to physical process

(B) It happens due to chemical process

(C) None of these

 

Answer Key:

  1. (C)
  2. (B)
  3. (A)
  4. (C)
  5. (B)
  6. (D)
  7. (A)
  8. (B)
  9. (C)
  10. (A)