Question

Explain why magnesium hydroxide has the formula Mg(OH)2

Answer 1

It’s just the way god created it, you can’t blame magnesium.

Answer 2

This is because magnesium has a 2+ charge whereas hydroxide has a 1- charge so you'd need 2 hydroxides to balance out the charges

Mg2+ OH-
OH-

2+. 2-

So Mg(OH)2. 2 hydroxide molecules and one magnesium