Conservation of mass

Question 1

According to the Conservation of mass, what happens in a chemical reaction?

Answer 1

Chemical reactions involve breaking chemical bonds between reactant molecules (particles) and forming new bonds between atoms in product particles (molecules). The number of atoms before and after the chemical change is the same but the number of molecules will change.

Question 2

Why is mass conserved in a reaction?

Answer 2

the new substances created are composed of atoms that were present in the reactants