Explain how the law of conservation of mass is at work in various chemical equations
Be able to justify how the law of conservation of mass works in a given chemical equation using numerical data from the question to support your response

This law states that, despite chemical reactions or physical transformations, mass is conserved — that is, it cannot be created or destroyed — within an isolated system. In other words, in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.

I looked this up but hope it helps!