Question

What mass of hydrated copper(II) sulfate
(CuSO4·5H2O) is needed to prepare one liter
of a 0.6675 molar solution of CuSO4?
a. 0.675 g
b. 166.7 g
c. none of these
d. 107.8 g
e. 10.8 g

Answer 1

Do you want 0.6675 M CuSO4.5H2O or do you want 0.6675 M CuSO4?
mols CuSO4.5H2O needed = M x L = ?
Then grams CuSO4.5H2O = mols CuSO4.5H2O x molar mass CuSO4.5H2O.

Answer 2

i think its 0.6675 M CuSO4

Answer 3

The answer is listed for grams CuSO4.5H2O but not for CuSO4.
Just follow the two equations I gave you in the first post to work the problem. Post your work if you don't understand.

Answer 4

so what i did was:
x=(.6675M)*(159.609 g/mol) which got me 106.539

Answer 5

But that isn't one of the choices.
Do 0.6675 M x molar mass CuSO4.5H2O. That looks like b to me. What do you think?

Answer 6

yup, i got 166.668

Answer 7

its 166.7