State the law of conservation of mass. then apply the law to this question: what would be the total mass of the products of a reaction in which 25 grams of table salt ( sodium chloride) decomposes into the elements sodium and chlorine?

Law of conservation of mass: according to this law that for a closed system where there no possibility of addition of loss of mass / energy, the mass of system will remains the same

Also, the mass of reactants is equal to the mass of products

Or

We cannot create mass or we cannot destroy mass

So if we have started with 25 grams of sodim chloride it will decompose to give total mass of product equal to 25 grams only