Which of the following actions results in a chemical change?

Burning rice is an example of a chemical change because it involves a transformation in the composition of the material. When rice is burned, it reacts with oxygen in the air, leading to the combustion process that produces new substances, such as carbon dioxide, water vapor, and ash. This transformation is irreversible, meaning you cannot turn the burned rice back into its original state of uncooked rice.

In contrast, boiling water, adding salt to water, and melting butter are all physical changes. Boiling water and melting butter involve changes in state (liquid to gas or solid to liquid) but do not alter the chemical composition of the substances involved. Similarly, when salt is added to water, it dissolves, but both the salt and the water retain their individual chemical identities; they can be separated back into their original forms.