(Solved): Which of the following compounds is an example of a hydrate? \( \mathrm{Ca}(\mathrm{OH})_{2} \) The ...

Which of the following compounds is an example of a hydrate? \( \mathrm{Ca}(\mathrm{OH})_{2} \) They are all hydrates. \( \mathrm{H}_{2} \mathrm{O}_{\oplus} \) \( \mathrm{FeSO}_{4} \cdot 4 \mathrm{H}_{2} \mathrm{O} \) \( \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH} \)