Changes Around Us Book Back Questions 6th Science Lesson 10
6th Science Lesson 10
10] Changes Around Us
Book Back Questions with Answer and Do You Know Box Content
Do You Know?
The change of state from solid to gas directly is called sublimation. Ex: Camphor
Water is known as the universal solvent. It dissolves a wide range of substance.
Choose the best answers:
1. When ice melts to form water, change occurs in its
(a) Position
(b) Colour
(c) State
(d) Composition
2. Drying of wet clothes in air is an example of
(a) Chemical change
(b) Undesirable change
(c) Irreversible change
(d) Physical change
3. Formation of curd from milk is
(a) A reversible change
(b) A fast change
(c) An irreversible change
(d) An undesirable change
4. Out of the following an example of a desirable change is
(a) Rusting
(b) Change of seasons
(c) Earthquake
(d) Flooding
5. Air pollution leading to Acid rain is a
(a) Reversible change
(b) Fast change
(c) Natural change
(d) Human made change
Fill in the blanks:
1. Magnet attracts iron needle. This is ___________ change. (a reversible / an irreversible)
2. Boiling of egg results in ______________ change. (a reversible / an irreversible)
3. Changes that are harmful to us are _______________ (desirable / undesirable)
4. Plants convert Carbon-di-oxide and water into starch. This is an example of _____________ change. (natural / human made)
5. Bursting of fire crackers is a _________ change whereas germination of seeds is a _____________ change. (slow / fast)
State true or false. If false, correct the statement:
1. Growing of teeth in an infant is slow change.
2. Burning of match stick is a reversible change.
3. Change of New moon to Full moon is human made.
4. Digestion of food is a physical change.
5. In a solution of salt in water, water is the solute.
Complete the analogy:
1. Curdling of milk: irreversible change :: Formation of clouds: _____________ change
2. Photosynthesis: ______________ change :: burning of coal: Human – made change
3. Dissolving of glucose: reversible change :: Digestion of food: ______________ change
4. Cooking of food: desirable change :: decaying of food: _________________ change
5. Burning of matchstick: _______________ change :: Rotation of the Earth: Slow change
Circle the odd one out. Give reason for your choice:
1. Growth of a child, Blinking of eye, Rusting, Germination of a seed
2. Glowing of a bulb, lighting of a candle, breaking of a coffee mug, curdling of milk
3. Rotting of an egg, condensation of water vapour, trimming of hair, ripening of fruit
4. Inflating a balloon, popping a balloon, fading of wall paint, burning of kerosene
Answers:
Choose the best answer:
1. State 2. Physical change 3. An irreversible change 4. Change of seasons 5. Human made change
Fill in the blanks:
1. A reversible change 2. An irreversible 3. Undesirable 4. Natural 5. Fast, Slow
Say True or False:
1. True
2. False
Correct Statement: Burning of matchstick is an irreversible chemical change.
3. False
Correct Statement: Change of New moon to Full moon is a natural change.
4. False
Correct Statement: The digested food undergoes chemical change.
5. False
Correct Statement: In a solution of salt in water, water is the solvent.
Complete the analogy:
1. Reversible change 2. Natural 3. Irreversible change 4. Undesirable change 5. Fast
Circle the odd one out. Give reason for your choice:
1. Blinking of eye. All the others are slow changes
2. Curdling of milk. All the others are fast changes.
3. Trimming of hair. All the others are slow changes.
4. Fading of wall paint. All the others are fast changes.