The following statements characterize a chemical reaction, EXCEPT a. The atoms of the substance rearrange, but the total number of atoms remain the same after the reaction. b. a change in odor c. a change in the total mass of the product d. Energy is involved in the reaction that is either absorbed or released.

C. a change in the total mass of the product

Explanation:

A chemical reaction is a reaction that alters the chemical composition of the substances involved. Based on the options in this question, a chemical reaction possess the following features:

- The atoms of the substance called reactants are rearranged into products but the total number of atoms remain the same after the reaction.

- A change in odor occurs as one of the indicators that a chemical reaction has taken place.

- Energy is either absorbed (endothermic) or released (exothermic) in the chemical reaction.

However, one untrue option is that "there is a change in the total mass of the product". The total mass of a chemical reaction does not change i.e. remains the same, before or after the reaction in accordance to the law of conservation of mass.