What is the formula for barium hydroxide?

##Ba(OH)^2##

Barium is an element in Group 2, so it has two , 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.

##Ba^(2+)## and ##(OH)^(2-)##

##Ba^(2+)## ##(OH)^(2-)## ##(OH)^(2-)##

As seen from above, one barium ion and two hydroxide ions form barium hydroxide. Thus, the formula of barium hydroxide is ##Ba(OH)^2##