Molecular weight of $\mathit{CuS}{O}_4.5H_{2}O$ is equal to

Molecular weight of $\mathit{CuS}{O}_4.5H_{2}O$ is equal to $249.5u$.
$\mathit{CuS}{O}_4$ has a molecular mass of $5H_{2}O$, which is calculated as follows: $Atomic\mathit{ }mass\mathit{ }of\mathit{(}\mathit{Cu}+S+(4O)+5[2\mathit{ }\mathit{H }+\mathit{ }O]$
$\Rightarrow 63.5+32+(4\times 16)+5(2+16)g$
$\Rightarrow 63.5+32+64+90\mathit{ g}$
$\Rightarrow 249.5\mathit{ g}$