Dr bob for this question :Calculate the molar solubility of manganese II hydroxide in ph 12.85 solution. The Ksp is 2.1 x 10^-13 but I can't solve for x thanks.

Question

Dr bob for this question :Calculate the molar solubility of manganese II hydroxide in ph 12.85 solution.  The Ksp is 2.1 x 10^-13 but I can't solve for x thanks.

DrBob222 · Answer

Ksp = (Mn^2+)(OH^-)^2 2.1E-13 = (x)(2x + 0.07)^2 To avoid a quadratic assume 2x + 0.07 = 0.07 2.1E-13 = (x)(0.0708)^2 x = (2.1E-13/(0.0708)^2 etc.