To find the molecular weight of sodium chloride, we simply add the atomic weights of sodium and chloride. So 23 grams/mol plus 35.5
grams/mol gives us 58.5 grams/mol. This is a molecular weight of sodium chloride. Now, to find a number of moles, we divide our molecular weight or we divide our amount that we have by our molecular weight. The grams cancel, the moles go on top. So 9.47
divided by 58.5 gives us 0.16 moles of sodium chloride.