Question

Copper(II) sulfate forms a bright blue hydrate with the formula CuSO 4 ⋅ n H 2 O ( s ) . If this hydrate is heated to a high enough temperature, H 2 O ( g ) can be driven off, leaving the grey‑white anhydrous salt CuSO 4 ( s ) . A 14.220 g sample of the hydrate was heated to 300 ∘ C . The resulting CuSO 4 ( s ) had a mass of 8.9935 g . Calculate the val

Answer 1

Answer:

The value of n in the hydrate formula is 5 ,$CuSO_4.5H_2O$.

Explanation:

$CuSO_4.nH_2O\rightarrow CuSO_4+nH_2O$

Mass of hydrate of copper sulfate = 14.220 g

Moles of hydrate of copper sulfate =$\frac{14.220 g}{(159.5+n\times 18) g/mol}$

Mass of copper sulfate after heating = 8.9935 g

Moles of copper sulfate = $\frac{8.9935 g}{159.5 g/mol}$

$\frac{14.220 g}{(159.5+n\times 18) g/mol}=\frac{8.9935 g}{159.5 g/mol}$

Solving for n, we get:

n = 5

The value of n in the hydrate formula is 5 ,$CuSO_4.5H_2O$.