Question

3. Students measured the mass of the reactants and products for a combustion reaction they observed.

Answer 1

Answer:

A. Students made a measurement error, because ending with more products is impossible.

Explanation:

The law of conversation of matter tells us that in a chemical reaction, matter is never created or destroyed, it's simply converted from one form to another. So the mass of reactants should always equal the mass of the products in a chemical reaction. If there is excess mass in the product, the students have made an error of some kind.