EASY
Earn 100

What are irreversible changes? Give examples.

Important Questions on Changes Around Us

MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
When a piece of coal is burnt, it turns to ash. Identify it is a Physical change or Chemical change.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Differentiate between reversible and irreversible changes.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
What happens to an apple if it is cut and left in the open air? What type of change is this?
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Give two examples each to explain the difference between changes that can be reversed and those that cannot be reversed.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes

Can you get back the matchstick from the ash left after it is burnt? Why or why not?

MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
When wood is kept in contact with water for a long time, it rots. Identify it is a physical or chemical change.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
When a candle is lit, the wax melts. Identify it is a physical or chemical change.
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Following are few examples of changes: 
(a) The spilling of water from a bucket
(b) The burning of a candle
(c) The breaking of a glass bottle
(d) The digestion of food
(e) The melting of an ice cube
Which of the changes listed above can be reversed?
 
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Which of the following is an example of a reversible change?
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
When the sun shines on a puddle of water, the water evaporates. Identify it is a physical change or chemical change.
HARD
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Seema bought a new skirt for school. When she came home, she realised that it was too long, so she asked her mother to hem it. What kind of change is this?
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Which of the following is an example of irreversible change?
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
When jelly cubes are heated, they melt. Identify it is a physical or chemical change.
 
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
 When a whisked egg is heated, it scrambles. Identify it is a physical or chemical change.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
What do you understand by a reversible change? Give an example.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Is converting wood into sawdust a reversible change? Give a reason in support of your answer.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Select the material that undergoes the change.
Boiling an egg.
EASY
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes

Mention if the change is reversible change or irreversible change. 

Making a mistake while knitting a sweater is a _____.

MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Why cannot permanent change be reversed? When milk is turned into curd, its taste changes. Why? Can we change the curd back into milk?
MEDIUM
Science>Chemistry>Changes Around Us>Reversible and Irreversible Changes
Kumar, the potter, used clay to shape a vase on his wheel. Then he baked it in the oven. What kinds of changes are these? Give reasons.