Answer to Question #337773 in General Chemistry for soph

Question

2. At a certain temperature a saturated solution of BaF2 has a concentration of 4.59 x 10-2 M. What is the Ksp for BaF2 at this temperature? (3 marks)

3. What is the concentration of the ions present in a saturated Cd(OH)2 solution? Ksp = 5.3 x 10-15. (4 marks)

Answer 1

2.BaF₂ <===> Ba²⁺ + 2F^-

K_sp = [Ba²⁺][2F^-]²

K_sp = 4.59 x 10^-2 M * (2•4.59 x 10^-2 M)² = 3.87x10^-4

3.Cd(OH)₂ <===> Cd²⁺ + 2OH^-

K_sp = [Cd⁺][2OH^-]²

[Cd⁺] - x; [OH^-]² - 2x

5.3 x 10^-15 = x • (2x)²

5.3 x 10^-15 = 4x³

x³ = 1.325 x 10^-15

x = 1.098 x 10⁵

[Cd⁺] - 1.098 x 10⁵M

[OH^-]² - (2•1.098 x 10⁵) = 2.196x10⁵ M