Question

I still need help with this problem...

Calculate the concentration of the solution

the molality of hydroxide ions in a solution prepared from 9.16 g of barium hydroxide dissolved in 179 g of water

I do not know how to approach this...I keep doing something wrong.

Answer 1

It's easy to post a question and say you're doing something wrong. You should post your work and let us see what you are doing wrong. We can catch hidden errors that way. Here is what you do.
Convert 9.16 g Ba(OH)2 to moles.
There are two OH^- per mole Ba(OH)2; therefore, moles Ba(OH)2 x 2 = moles OH^-
Then moles OH^-/kg water = m of OH^-