Question

in the chemical reaction below, calcium metal and water react to form calcium hydroxide and hydrogen gas. calcium metal + water → calcium hydroxide + hydrogen gas calcium and water are the reactants in this chemical reaction, whereas calcium hydroxide and hydrogen gas are the products that are formed. once the reaction reaches completion, ○a. the total mass of the products will be greater than the original mass of the reactants ○b. the total mass of the products will be equal to the original mass of the reactants. ○c. the products of the reaction will have changed back into the reactants. ○d. the total mass of the products will be less than the original mass of the reactants

Explanation:

According to the law of conservation of mass in chemical reactions, the total mass of reactants is equal to the total mass of products. In this reaction, calcium metal and water (reactants) react to form calcium hydroxide and hydrogen gas (products). The law of conservation of mass applies here. Option A is incorrect because mass is conserved, not increased. Option C is incorrect as the reaction is shown as going to completion (forming products, not reverting). Option D is incorrect as mass is not lost.

Answer:

B. the total mass of the products will be equal to the original mass of the reactants.