What is the formula mass of copper sulfate pentahydrate [CuSO₄·5H₂O]? Be sure to add the water of hydration, which is the 5H₂O part (water surrounding the copper sulfate).
a) 249.7 g/mol
b) 249.7 g/mol
c) 249.7 g/mol
d) 249.7 g/mol