Changes Around Us

Which of the following involves a fast chemical change?

• Burning of Matchstick

• The rusting of Iron

• Ripening of fruit

• The growth of Humans

Statement 1: A change that can be reversed is called a reversible change.

Statement 2: Falling of leaves from a tree is a reversible change

• Both statements 1 and 2 are correct

• Both statements 1 and 2 are incorrect

• Statement 1 is correct and Statement 2 is incorrect

• Statement 1 is incorrect and Statement 2 is correct

Which of the following is not an irreversible change?

• The ripening of mango

• The curdling of milk

• The condensation of water vapor

• The rusting of iron

A chemical change is a reversible change

• True

• False

• None of these

• No idea

The heating of wax is an irreversible change

• True

• False

• No idea

• None of the above

Which of the following is a chemical change?

• Evaporation of water

• Burning of fuels

• Moving of a wheel

• Breaking of a brick

A process in which an object becomes smaller or shrinks is called

• chemical change

• irreversible change

• contraction

• expansion

Which of these changes cannot be reversed?

• Hardening of cement

• Freezing of ice cream

• Opening a door

• Melting a chocolate

An iron ring is heated. Which of the following statements about it is incorrect?

• The ring expands.

• The ring almost comes to the same size on cooling.

• The change, in this case, is reversible.

• The change cannot be reversed.

What are the changes in which a new substance is formed called?

• Physical changes

• Chemical changes

• Fast changes

• Slow changes