How many grams of sodium sulfate do you need to create 750 mL of a 0.250 M solution of sodium sulfate

Answer 1

How many mols do you need? That's M x L = ?
Convert mols to grams. g = mols x molar mass.

Answer 2

n = MV
n = (0.250 M)(0.750 L) = 0.1875 mol

m = n * MM
m = 0.1875 mol * 142.04 g/mol
m = 27 g