What about this question?
Calculate the mass (g) of PbSO4 that will dissolve in 2000 mL of 0.0694 M K2SO4 solution. The equation represents the solubility process.
PbSO4 (s) Pb2+ (aq) + SO42- (aq)
Ksp = 1.7 x 10-8
Also other information
Answer they gave: 0.000148571182
Molsr Mass: PbSO4 303.26
Write the expression for Ksp.
Ksp = 1.7 x 10^-8 = (Pb^+)(SO4^-2)
(Pb^+2)(0.0694)=Ksp
Solve for (Pb^+2) = ??
(PbSO4) = (Pb^+2)
solubility PbSO4 = ?? from above.
M x L = moles = ??M x 2 L
grams = moles x molar mass.
That's 0.00014857 but you need to round that to 2 s.f. which is 0.00015 grams.
To calculate the mass of PbSO4 that will dissolve in 2000 mL of 0.0694 M K2SO4 solution, we need to use the information about the solubility product constant (Ksp).
Step 1: Write out the balanced equation for the solubility process:
PbSO4 (s) ⟶ Pb2+ (aq) + SO42- (aq)
Step 2: Write the expression for the Ksp using the concentrations of the ions:
Ksp = [Pb2+] * [SO42-]
Step 3: Determine the molar concentrations of Pb2+ and SO42- ions present in the solution.
Since K2SO4 is a strong electrolyte, it dissociates completely in water:
K2SO4 ⟶ 2 K+ + SO42-
This means the concentration of SO42- in the solution is twice the molarity of K2SO4: [SO42-] = 2 * 0.0694 M = 0.1388 M
However, since PbSO4 is sparingly soluble, we can assume that the concentration of Pb2+ is negligibly small initially.
Step 4: Plug the concentrations of Pb2+ and SO42- into the Ksp expression:
1.7 x 10^(-8) = [Pb2+] * 0.1388
Step 5: Solve for [Pb2+]:
[Pb2+] = (1.7 x 10^(-8)) / 0.1388
[Pb2+] ≈ 1.22 x 10^(-7) M
Step 6: Calculate the moles of PbSO4 that will dissolve:
Since the ratio of ions in the solubility equation is 1:1, the molar concentration of PbSO4 also equals [Pb2+]. Therefore, the moles of PbSO4 dissolved in the solution is:
moles = [Pb2+] * (volume in L)
moles = (1.22 x 10^(-7) M) * (2 L)
moles ≈ 2.44 x 10^(-7) mol
Step 7: Calculate the mass of PbSO4:
mass = moles * molar mass of PbSO4
The molar mass of PbSO4 is 207.2 g/mol.
mass = (2.44 x 10^(-7) mol) * (207.2 g/mol)
mass ≈ 5.06 x 10^(-5) g
Therefore, the mass of PbSO4 that will dissolve in 2000 mL of 0.0694 M K2SO4 solution is approximately 5.06 x 10^(-5) g.
To calculate the mass of PbSO4 that will dissolve in a given volume of K2SO4 solution, we need to use the solubility product constant (Ksp) and the molar concentration of K2SO4 solution.
First, let's understand the meaning of the Ksp value. Ksp represents the equilibrium constant for the dissociation of an insoluble compound (in this case, PbSO4) into its constituent ions (Pb2+ and SO42-). The higher the Ksp value, the more soluble the compound is.
To calculate the mass of PbSO4, we need to follow these steps:
1. Write the expression for Ksp using the concentrations of the constituent ions.
Ksp = [Pb2+][SO42-]
2. Determine the concentration of the ions in the solution based on the molar concentration of the K2SO4 solution.
Since K2SO4 dissociates into two K+ ions and one SO42- ion, the concentration of SO42- is twice the molar concentration of K2SO4.
Concentration of SO42- = 2 * 0.0694 M = 0.1388 M
3. Use the Ksp expression to calculate the concentration of Pb2+.
Ksp = [Pb2+][SO42-]
1.7 x 10^-8 = [Pb2+][0.1388]
[Pb2+] = 1.7 x 10^-8 / 0.1388
4. Calculate the moles of PbSO4 using the concentration of Pb2+.
Moles of PbSO4 = [Pb2+] * volume of solution in liters
Convert the volume from milliliters (mL) to liters (L): 2000 mL = 2000/1000 = 2 L
Moles of PbSO4 = ([Pb2+] * 2)
5. Finally, calculate the mass of PbSO4 using its molar mass.
Molar mass of PbSO4 = atomic mass of Pb + atomic mass of S + 4 * atomic mass of O
Molar mass of PbSO4 = (207.2 g/mol + 32.1 g/mol + 4 * 16.0 g/mol)
Mass (g) of PbSO4 = Moles of PbSO4 * Molar mass of PbSO4
By following these steps, you should be able to calculate the mass of PbSO4 that will dissolve in the given K2SO4 solution.