Step-by-step explanation:
If u mix 1g of salt with 100 ml of water, both dissolves but at the same time the mass of the solution increases.
According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants. The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction