Describe each of the following as a physical or chemical property. a. Neon is a colorless gas at room temperature. b. Apple slices turn brown when exposed to air. c. Phosphorus will ignite when exposed to air. d. At room temperature, mercury is a liquid.

Neon is a colorless gas at room temperature: Physical property

At room temperature, mercury is a liquid: Physical property

Apple slices turn brown when exposed to air: Chemical property

Phosphorus will ignite when exposed to air: Chemical property

Explanation:

Physical property is defined as the property of a substance which becomes evident during physical change in which there is alteration in shape, size etc. No new substance gets formed during physical change.

Example:  Neon is a colorless gas at room temperature

At room temperature, mercury is a liquid.

Chemical property is defined as the property of a substance which becomes evident during chemical change in which a change in chemical composition takes place. A new substance is formed in these reactions.

Example: Apple slices turn brown when exposed to air: It undergoes oxidation which is a chemical change

Phosphorus will ignite when exposed to air: It undergoes oxidation which is a chemical change