Form 300 mL of 0.25 M Copper 2 sulfate pentahydrate

Answer 1

You want how many mols? That's M x L = mols.
Then mols = grams/molar mass. You know molar mass and mols, solve for grams.
Dissolve that many g CuSO4.5H2O in some water and make to exactly 300 mL with distilled water.