Question

In the following list, decide whether each item is a physical or a chemical change: a. liquid water freezes into solid ice b. wood burns to ashes c. a window shatters when hit with a rock d. an old car sits in a junkyard and rusts e. a cup of hot chocolate gives off steam

Answer 1

Explanation:

A property that does not bring any change in chemical composition of a substance are known as physical properties.

For example, shape, size, mass, volume, density, hardness etc of a substance are all physical properties.

On the other hand, a property that changes chemical composition of a substance is known as chemical property.

For example, precipitation, reactivity, toxicity etc are chemical property.

Therefore, given changes are correctly matched as follows.

• liquid water freezes into solid ice - physical change

• wood burns to ashes - chemical change

• a window shatters when hit with a rock - physical change

• an old car sits in a junkyard and rusts - chemical change

• a cup of hot chocolate gives off steam - physical change