Answer: Yes, the mass of the reactants always equal to the mass of the products in a chemical reaction.
Explanation:
In a balanced chemical reaction, the mass of reactants is always equal to the mass of product that is a chemical reaction follows follows 'Law of Conservation of Mass'.
The law states that ' in a chemical reaction mass can neither be created nor be destroyed.
For example: 
Mass of the reactants = Mass of products

36 amu = 36 amu
Yes, the mass of the reactants always equal to the mass of the products in a chemical reaction.