If a chemical reaction occurs, the properties of substances before and after the substances interact must be

different

Explanation:

A chemical reaction may be defined as the process or method by which a substance undergo a change in their structure chemically when reacting with some other substance and acquiring the property of both or sometimes forms a new substance. It leads to the chemical transformation of the chemical substance to some another substance.

The properties of the new substance formed is different form the parent substance before the reaction.

Thus, when chemical reaction occurs, the properties of the substances before the reaction and after the reaction takes place is different.

they all get energy from eating other animals, dead animals to be more precise.

hienas tends to steal pray from other animals. crows and vultures tend to eat dead animals and leftovers.

hope it ,

bioteacher101