At a certain temperature, the solubility of barium chromate (#BaCrO_4#) is #1.8 x 10^-5# mol/L. What is the Ksp value at this temperature?

1 Answer
Oct 27, 2016

#K_(sp)# #=# #[Ba^(2+)][CrO_4^(2-)]# #=# #(1.8xx10^-5)^2#

Explanation:

We write the solubility expression in this way:

#BaCrO_4(s) rightleftharpoons Ba^(2+) + CrO_4^(2-)#

Now #K_(sp)# #=# #[Ba^(2+)][CrO_4^(2-)]# #=# #(1.8xx10^-5)^2# #=# #3.24xx10^-10.#

Why do we square this value? We were quoted the solubility of barium chromate. Because the solubility represents the concentrations of chromate ion and barium ion.