Question

The solubility product for barium sulfate is 1.1*10^-10. Calculate the molar solubility of barium sulfate.

1) 5.5*10^-11 mol/L

2) 1.1 *10^-5 mol/L

3) 2.1*10^-5 mol/L

4) 1.1*10^-10 mol/L

5) 2.2*10^-10 mol/L

I don't understand how to solve this. I'm stuck. Can anyone help me soon as possible as fast? Thank you.

Answer 1

Given the solubility product for barium sulfate, BaSO₄ is , K_sp = 1.1x10^-10

Let S mol/L be the solubility of BaSO₄

BaSO₄ Ba²⁺ + SO₄^2-

1 mole of BaSO₄ produces Ba²⁺ + SO₄^2-

[Ba²⁺ ] = [SO₄^2- ] = [BaSO₄] = S

Solubility product, K_sp = [Ba²⁺][SO₄^2-]

                                 = S x S

          1.1x10^-10 = S²

                              S = 1.1x10^-5 mol/L

Therefore option (2) is correct