Which of the Following Is Not an Example of a Chemical

Multiple Choice

Which of the following is not an example of a chemical change?

A) Water becomes purple as Kool-Aid is dissolved in it.
B) Aluminum turns white after prolonged exposure to air.
C) A piece of charcoal becomes white after it burns.
D) Magnesium burns in air to make magnesium oxide.
E) Zinc metal reacts with hydrochloric acid to form zinc chloride and hydrogen gas.