To prepare 100 mL of a 0.5 M solution of CuSO4 using water as the solvent. Calculate the amount of solid needed.

Explanation:

100 mL of a .5 M solution

= 0.1 L of .5 M solution

This solution will contain .1 x .5 mole of solute

= .05 mole of solute

molecular weight of CuSO₄

= 63.5 + 32 + 64

= 159.5 gm

one mole of CuSO₄  = 159.5 gm

.05 mole = 159.5 x .05 gm

= 7.975 gm

7.975 gm of CuSO₄ will be required .