What is the empirical formula of stannous fluoride, the first fluoride compound added to toothpaste to protect teeth against decay? Its mass percent composition is 24.25% F, 75.75% Sn.

Video transcript

Hey everyone. We're asked to provide the correct empirical formula for a substance containing 47.90% of sink and 52.02% of chlorine. The key to this question is to recognize that we have 100% of our compound present. So we can go ahead and assume that we have 100 g. This will make it easier for us to convert from percentages into grams. So starting off with our zinc, we have 47.98 g of zinc and we want to convert this into moles in order to get our empirical formula. Looking at our periodic table, We know that sinks atomic mass is going to be 65. g of zinc per one mole zinc. And when we calculate this out, we end up with a total of 0.7338 mol of zinc. Next looking at our corinne, We have 52.02 g of chlorine. And using our dimensional analysis we have 35.45 - seven g of chlorine per one mole of chlorine. When we calculate this out, we end up with a total of 1.467 mol of chlorine. Now, in order to get our empirical formula, we're going to need to divide our values by the least amount of moles present here. In this case, it's going to be 0.7338. So when we do that we get one of zinc and we also get two of chlorine, this means our empirical formula is going to be ZN CL two, and this is our final answer. So I hope this made sense and let us know if you have any questions.