Law of conservation of mass

The law of conservation of mass states that matter cannot be created or destroyed in a chemical or physical process. This means that the total mass of substances involved in a reaction remains the same before and after, even if their forms change. For example, when wood burns, it turns into ash, gases, and heat, but the combined mass of all these products equals the original mass of the wood plus any oxygen consumed. Essentially, matter is conserved through transformation, ensuring the total amount stays constant throughout any process.