The solubility of MnS was found to be 0.000963 g per 700 mL of water. Calculate the solubility product constant (Ksp) for MnS.
MnS (s)=Mn2+ (aq) + S2- (aq)
Convert solubility in g/700 mL to moles/L, substitute M into Ksp and solve.
thanks..andy
To calculate the solubility product constant (Ksp) for MnS, we need to first determine the concentration of the dissolved ions, which are Mn2+ and S2- in this case.
Given information:
Mass of MnS dissolved = 0.000963 g
Volume of water = 700 mL
Step 1: Convert the volume of water to liters:
Since 1 L = 1000 mL, we have
Volume of water = 700 mL / 1000 mL/L = 0.7 L
Step 2: Calculate the concentration of each ion:
Concentration of Mn2+ = Moles of Mn2+ / Volume of water (in L)
Concentration of S2- = Moles of S2- / Volume of water (in L)
Step 3: Determine the number of moles of each ion:
To find the number of moles, we need to know the molar mass of MnS.
Molar mass of Mn = 54.94 g/mol
Molar mass of S = 32.06 g/mol
Molar mass of MnS = Molar mass of Mn + Molar mass of S
= 54.94 g/mol + 32.06 g/mol
= 87 g/mol
Number of moles of MnS = Mass of MnS dissolved / Molar mass of MnS
= 0.000963 g / 87 g/mol
Step 4: Calculate the concentrations of each ion:
Since MnS dissociates into one Mn2+ ion and one S2- ion, the number of moles of Mn2+ and S2- is the same.
Concentration of Mn2+ = Concentration of S2- = Number of moles of MnS / Volume of water (in L)
Step 5: Calculate the solubility product constant (Ksp):
Since MnS dissociates into one Mn2+ ion and one S2- ion, we have:
Ksp = [Mn2+] * [S2-]
Substituting the concentrations we calculated in Step 4 into the equation, we have:
Ksp = (Concentration of Mn2+) * (Concentration of S2-)
Let's perform the calculations:
Number of moles of MnS = 0.000963 g / 87 g/mol = 0.0000111 mol
Concentration of Mn2+ = Concentration of S2- = 0.0000111 mol / 0.7 L = 0.0000159 M
Thus, the solubility product constant (Ksp) for MnS is 1.59 x 10^-5.