Which of these is an example of a physical change? sugar, when heated, producing carbon dioxide and water solid ice, when heated, turning into liquid water sodium, when exposed to chlorine, forming sodium chloride aluminum, when heated in air, forming aluminum oxide

Option (b) is the correct answer.

Explanation:

When there is no change in chemical composition of a substance  then this change is known as physical change.

Where as when there is change in chemical composition of a substance then it is known as chemical change.

When sugar is heated, it results in the formation of carbon dioxide and water. This means that composition of sugar has changed thus, it is a chemical change.

When solid ice is melted, it turns into liquid. This shows that only state of water has changed. There is no change in chemical composition because when we freeze water then again liquid water changes into solid ice. Thus, it is a physical change.

When sodium reacts with chlorine then the reaction is as follows.

It shows that chemical composition of sodium has changed due to the formation of sodium chloride. Thus, it is a chemical change.

Also, when aluminium is is heated in air then it results in the formation of aluminium oxide. This means that the chemical composition of aluminium has changed.

Hence, we can conclude that out of the given options, solid ice, when heated, turning into liquid water is an example of a physical change.