Final answer:
The law of conservation of mass states that matter is neither created nor destroyed in a chemical reaction. The total mass of substances taking part in a chemical reaction is conserved during the reaction.
Step-by-step explanation:
The law of conservation of mass states that matter is neither created nor destroyed in a chemical reaction. This means that the total mass of substances taking part in a chemical reaction is conserved during the reaction. For example, when wood burns, the total mass of the soot, ashes, and gases produced is equal to the mass of the wood and oxygen that initially reacted.