If you measure the mass of all the reactants and compare it to the mass of all the products for a chemical reaction, what would you expect to find?

the mass of the reactants are the same as the mass of the products
the reactants always weigh more than the products
the products always weigh more than the reactants
elements do not have mass and cannot be measured for weight

The mass of the reactants is the same as the mass of the products, according to the law of conservation of mass.

According to the law of conservation of mass, the mass of the reactants in a chemical reaction is expected to be the same as the mass of the products. This means that the mass of the reactants and the mass of the products should be equal.