Answer:
To calculate the Ksp value, we need to use the solubility of magnesium phosphate. The given solubility is 0.036 g/100 mL.
Ksp represents the solubility product constant, which is the equilibrium constant for the dissolution of a sparingly soluble compound. In this case, we have magnesium phosphate (Mg3(PO4)2).
To calculate Ksp, we need to know the balanced equation for the dissolution of magnesium phosphate. The balanced equation is:
Mg3(PO4)2(s) = 3Mg2+(aq) + 2PO4^3-(aq)
Since the solubility is given in grams per 100 mL, we can convert it to moles per liter (mol/L).
First, let's calculate the molar solubility of
magnesium phosphate:
Molar solubility = (0.036 g/100 mL)/(molar mass of Mg3(PO4)2)
=(0.036 g/100 mL)/ (3 molar mass of Mg + 2 * molar mass of PO4)
= (0.036 g/100 mL)/(3*24.31 g/
mol + 2 * 94.97 g/mol)
= 4.92 x 10^(-5) mol/L
Now that we have the molar solubility, we can calculate the Ksp value using the formula:
Ksp = [Mg2+]^3 * [PO4^3-]^2
Substituting the molar solubility values:
Ksp = (4.92 x 10^-5))^3 - (4.92 × 10^-5))^2 = 1.04 x 10^(-38)
To calculate the pKsp value, we take the negative logarithm (base 10) of the Ksp value:
pKsp = -log10(1.04 x 10^(-38))
= 38.98
Rounded to two decimal places, the pKsp value is 38.98.
Therefore, the Ksp value at this
temperature is approximately 1.04 x 10^-38), and the pKsp value is approximately 38.98.