Question

How many grams of cobalt(II) sulfate, CoS04, must be dissolved to prepare 300. mL of a 0.172 M aqueous solution of the salt? g

Answer 1

Concentration of CoSO4 = 0.172 M = 0.172 mol/L

Volume of solution = 300 ml = 300 L / 1000 = 0.300 L

Number of moles of CoSO4 = 0.172 mol/L * 0.300 L = 0.0516 mol

Molar mass of CoSO4 = 155 g/mol

Mass of CoSO4 = 155 g/mol * 0.0516 mol = 8.0 g

Mass of cobalt(II)sulfate be dissolved = 8.0 g