Mg(OH)2 has a solubility of 9.0x10^-5 M. What is the value of Ksp for Mg(OH)2?

Mg(OH)2 has a solubility of 9.0x10^-5 M. What is the value of Ksp for Mg(OH)2?

1 Answer
Jun 2, 2016

Answer:

#K_"sp" = 2.9 × 10^"-12"#

Explanation:

The chemical equation for the equilibrium is

#color(white)(mmmmmm)"Mg(OH)"_2"(s)" ⇌ "Mg"^(2+)"(aq)" + 2"OH"^"-""(aq)"#
#"E:/mol·L"^"-1" color(white)(mmmmmmmmllm)x color(white)(mmmmmll)2x#

#K_"sp" = ["Mg"^(2+)]["OH"^"-"]^2 = x(2x)^2 = 4x^3#

#x = 9.0 × 10^"-5"#

#K_"sp" = = 4(9.0 × 10^"-5")^3 = 2.9 × 10^"-12"#