Question

Calculate the mass of the solid you must measure out to prepare 100 mL of 0.025 M CuSO4.

Note that this salt is a hydrate, so its formula is CuSO4⋅5H2O. You must include the waters of hydration when calculating the formula weights.

Would the following set-up yield the correct answer?

(100 mL CuSO4⋅5H2O) x (1 L CuSO4⋅5H2O / 1000 mL CuSO4⋅5H2O) x (0.025 mol CuSO4⋅5H2O / 1 L CuSO4⋅5H2O) x (249.7 g CuSO4⋅5H2O / 1 mol CuSO4⋅5H2O)

= 0.624 g CuSO4⋅5H2O

Any feedback is appreciated. Thanks!

Answer 1

CuSO4.5H2O

RMM=249.68

For 1000 ml of 1M need 249.68g

For 100 ml of 1 M need 24.968 g

For 100 ml of 0.025 M need 24.968 x 0.025 = 0.0624 g

Yes, agreed.

Answer 2

How many grams of S are needed to produce 10g of CuS?