What mass of solute is needed to make 210 mL of a 0.663 M MgF2 solution?

Question

i dont know how to find mass??
please help

Answer 1

First, use the molarity formula to solve for the number of moles. So multiply .210 L (210mL times 1000 to get to L) by .663 M, which will give you the number of moles of MgF2. Then, use the moles to convert to grams. So divide the number of moles by the molecular weight, which for MgF2 is 62.31 g/mol. This will give you the mass of solute.