Final answer:
The law of conservation of matter states that matter cannot be created or destroyed, only converted from one form to another. This means that the total mass of the products in a chemical reaction must equal the total mass of the reactants.
Step-by-step explanation:
The law of conservation of matter states that in any given system that is closed to the transfer of matter, the amount of matter in the system stays constant. This means that matter cannot be created or destroyed, only converted from one form to another. For example, when you burn a piece of wood, the wood is converted into ash, smoke, and gases, but the total mass of the products is equal to the mass of the wood.