MCQ Questions for Class 6 Science: Ch 6 Changes around us
1. In general, on heating metals _______
(a) Contract
(b) Expand
(c) Can expand or contract
(d) None of these
► (b) Expand
2. Which of the following is a reversible change?
(a) Burning of matchstick
(b) Changing of milk into curd
(c) Germination of seed
(d) Melting of ice
► (d) Melting of ice
3. Sea water is a
(a) Element
(b) Mixture
(c) Molecule
(d) Compound
► (b) Mixture
4. The changes in which new substance is formed is called
(a) Temporary change
(b) Biological change
(c) Chemical change
(d) Physical change
► (c) Chemical change
5. Which of the following is an example of physical change?
(a) Boiling of water
(b) Ripening of fruit
(c) Rusting of iron
(d) A bud turning into flower
► (a) Boiling of water
6. Growth in size of the body of an organism is a
(a) Physical and permanent change
(b) Physical and temporary change
(c) Chemical and temporary change
(d) Chemical and permanent change
► (a) Physical and permanent change
7. What is common among the following phenomena?
1. Blinking of traffic lights.
2. Rotation of blades of a fan.
3. Swinging of pendulum of a clock.
(a) All are chemical changes.
(b) All are periodic changes.
(c) All are undesirable changes.
(d) All are irreversible changes.
► (b) All are periodic changes.
8. Which of these is the smallest particle?
(a) A speck of dust
(b) An atom
(c) A water drop
(d) A molecule
► (b) An atom
9. Digestion of food is a
(a) Temporary change
(b) Periodic change
(c) Chemical change
(d) Physical change
► (c) Chemical change
10. Melting of ice into water is a
(a) Exothermic change
(b) Physical change
(c) Permanent change
(d) Chemical change
► (b) Physical change
11. Riya tore a sheet of paper into pieces and then burnt them. Identify the irreversible change taking place in the process.
(a) Tearing the sheet into pieces.
(b) Burning the pieces
(c) Both tearing and burning the pieces
(d) None of these
► (c) Both tearing and burning the pieces
12. Megha mixed some iron filings with sulphur powder in a China dish. She heated the contents of China dish. What did she observe during the experiment?
(a) There was no difference in the contents of China dish before and after heating.
(b) Before heating, iron filings and sulphur powder could be seen separately but after heating the content became black.
(c) Before heating, the iron filings and sulphur powder could not be seen separately.
(d) Before heating, the contents were black and after heating, iron filings and sulphur could be seen separately.
► (b) Before heating, iron filings and sulphur powder could be seen separately but after heating the content became black.
13. Rotation of fan blade is a
(a) Permanent change
(b) Undesirable change
(c) Non- periodic change
(d) Periodic change
► (d) Periodic change
14. A potter shapes pots out of clay (Process 1). He then bakes the pots in an oven (Process 2). Which of the following statements is correct?
(a) Process 1 is a reversible, physical change while process 2 is an irreversible, physical change.
(b) Process 1 is an irreversible, physical change while process 2 is an irreversible, chemical change.
(c) Process 1 is a reversible, physical change while process 2 is an irreversible, chemical change.
(d) None of these.
► (c) Process 1 is a reversible, physical change while process 2 is an irreversible, chemical change.
15. Which of the following is a reversible change?
(a) Curdling of milk
(b) Ripening of fruits
(c) Melting of ice
(d) Burning of wood
► (c) Melting of ice
16. In a chemical change
(a) Energy change do not occur
(b) Energy is either absorbed or given out
(c) Energy is always absorbed
(d) Energy is given out
► (b) Energy is either absorbed or given out
17. In exothermic reaction
(a) Heat is evolved
(b) No change in temperature
(c) Heat is absorbed
(d) All of these
► (a) Heat is evolved
18. Melting of ice is a
(a) Both physical and chemical change
(b) Physical change
(c) Periodic change
(d) Chemical change
► (b) Physical change
19. In physical changes
(a) New substance is formed
(b) Evolution of heat energy takes place
(c) No new substance is formed
(d) Release of light energy takes place
► (c) No new substance is formed
20. Chemical changes are
(a) Mostly reversible
(b) Always irreversible
(c) Always reversible
(d) Mostly irreversible
► (d) Mostly irreversible
21. In which one of the following kinds of changes no new substance are formed?
(a) Chemical changes
(b) Irreversible changes
(c) Physical changes
(d) All of these
► (c) Physical changes
22. Which of the following is an example of physical change?
(a) A bud turning into a flower
(b) Boiling of water
(c) Ripening of a tomato
(d) Rusting of iron
► (b) Boiling of water
23. Which types of changes are temporary?
(a) Non-periodic change
(b) Periodic change
(c) Physical change
(d) Chemical change
► (c) Physical change
24. Which of the following is a reversible change?
(a) Curdling of milk
(b) Ripening of fruits
(c) Melting of ice
(d) Burning of wood
► (c) Melting of ice
25. Burning of candle is
(a) Neither physical and chemical change
(b) Chemical change
(c) Both physical and chemical change
(d) Physical change
► (c) Both physical and chemical change
26. Souring of milk is a
(a) Periodic change
(b) Undesirable change
(c) Desirable change
(d) Physical change
► (b) Undesirable change
27. Mark the incorrect statement.
(a) Melting of wax is a physical change while burning of wax in a candle is a chemical change.
(b) Metals expand on heating while contract on cooling. Both are physical changes.
(c) Composition of matter changes during a chemical change while it remains same during a physical change.
(d) High and low tides in sea are the examples of non-periodic changes while growth of a tree is a periodic change.
► (d) High and low tides in sea are the examples of non-periodic changes while growth of a tree is a periodic change.
28. Which one is a periodic change
(a) Freezing of water
(b) Melting of ice
(c) Dissolving sugar in water
(d) Change in season
► (d) Change in season