Mn (OH) 2 has a molar solubility of 2.2 x 10 − 5 M. Calculate the Ksp value for Mn(OH) 2 .
To calculate the Ksp value for Mn(OH)2, we need to understand the relationship between molar solubility and Ksp.
The molar solubility (s) represents the concentration of a solute that can dissolve in a solvent to form a saturated solution. In this case, the molar solubility of Mn(OH)2 is given as 2.2 x 10^−5 M.
The Ksp (solubility product constant) is an equilibrium constant that measures the solubility of a slightly soluble compound in a saturated solution. It is determined by the stoichiometry of the balanced chemical equation for the dissolution of the compound.
The balanced chemical equation for the dissolution of Mn(OH)2 is:
Mn(OH)2 ⇌ Mn2+ + 2OH−
According to the equation, for every 1 mole of Mn(OH)2 that dissolves, 1 mole of Mn2+ and 2 moles of OH− ions are produced. Therefore, the Ksp expression for Mn(OH)2 can be written as:
Ksp = [Mn2+][OH−]^2
Using the molar solubility (s) values, we can substitute them into the Ksp expression:
Ksp = (s)(2s)^2 = 4s^3
Substituting the value of s = 2.2 x 10^−5 M into the equation, we can now calculate the Ksp value for Mn(OH)2:
Ksp = 4(2.2 x 10^−5)^3
Calculating this expression gives us the Ksp value for Mn(OH)2.