# What is the formula for barium hydroxide?

Jan 2, 2016

$B a {\left(O H\right)}^{2}$

#### Explanation:

Barium is an element in Group 2, so it has two valence electrons, and that it's charge is 2+.

Hydroxide is a polyatomic negative ion with a valency of 1, and that it's charge is 1-.

As barium is a metal while hydroxide is a non-metal, they combine to form an ionic compound.

To form a neutral compound, balance the positive and negative charges by applying LCM,and the number of positive and negative charges must be equal.

$B {a}^{2 +}$ and ${\left(O H\right)}^{2 -}$

$B {a}^{2 +}$ ${\left(O H\right)}^{2 -}$ ${\left(O H\right)}^{2 -}$

As seen from above, one barium ion and two hydroxide ions form barium hydroxide. Thus, the formula of barium hydroxide is $B a {\left(O H\right)}^{2}$