When a compound is broken down in the chemical reaction, its atoms are

A. used to form new compound

B. destroyed and new atoms are created

C. considered exothermic

A. used to form new compound

When a compound is broken down in the chemical reaction, its atoms are used to form new compound.

Answer: Option A

Explanation:

In a chemical reaction involving one or more compounds, the atoms in the compounds breaks and bombardment happens to create a new compound. The chemical formula of the new compound comes form its parent compound due to mixing of molecules.

Hence Option B is invalid as atoms are not destroyed to create a new molecule. All chemical reactions are not exothermic hence option C is invalid.