Question

what does conserving mass mean in a chemical equation?
there are more of each type of atom on the reactant side than on the product side.
there are more of each type of atom on the product side than on the reactant side.
there is an unequal number of each type of atom on both sides of the equation.
there is equal number of each type of atom on the reactant and product side.

Explanation:

According to the law of conservation of mass, in a chemical reaction, matter is neither created nor destroyed. This means that the number of each type of atom must be the same on both the reactant and product sides of a chemical equation. If there were more atoms on one side (reactant or product) or an unequal number of atoms on both sides, it would violate this fundamental law. So, conserving mass in a chemical equation implies an equal number of each type of atom on the reactant and product side.

Answer:

There is equal number of each type of atom on the reactant and product side.