in this example question. It says how many grams of water vapor will form if 25 brands of hydrogen gas mixes with 12 g of oxygen gas. Now, applying what we just learned about the law of conservation of Mass. This is gonna be too bad, because remember, it says that the mass, the total mass of reactant, will equal the total mass of products. Here we have the masses of the reactions, which are 25 12. So we add them together. That will give us the total mass of product that could potentially form. So this answer here would be 37 g of products. Now, if we want to follow the law on the rules for significant figures, Technically, this has three sig figs, and this has three sig figs. So the better answer would be 37.0 g of water vapor, which is just water as a gas. So just remember, if we're just simply applying the law of conservation of Mass, just remember the amount of reacting Sequels of my amount of products. Now, later on, when we go into more advanced forms of calculations with chemical reactions, we're going to see, that's not always true. In those cases, we learn new mechanics and new approaches to enter those particular type of questions.