How to choose the correct name for calcium sulfate based on a calculations of the crystallisation water included?
From my calculations

\begin{align}
x &amp;= \frac{M(\ce{CaSO4}) \times \left[m(\ce{CaSO4 * xH2O}) - m(\ce{CaSO4})\right]}{M(\ce{H2O}) \times m(\ce{CaSO4})} =\\ 
&amp;= \frac{\pu{136.14 g mol-1} \times (\pu{1.77 g} - \pu{1.07 g})}{\pu{18.02 g mol-1} \times \pu{1.07 g}} =\\
&amp;= 4.94,
\end{align}

which gives $\ce{CaSO4* 5 H2O}$, calcium(II) sulfate pentahydrate.