Alright, so here is the problem, and I calculated A through D...Can someone help me on D please? I'm not good at explaining things...Please and thank you, it will be much appreciated!
A saturated solution of hydroxide is prepared and the excess solid strontium hydroxide is allowed to settle. A 25.0-mL aliquot of the satuared solution is withdrawn and transferred to an erlenmeyer flask, and two drops of methyl orange indicator are added. A 0.073 M HCL solution (titrant) is dispensed from a buret into the solution ( analyte). The solution turns from yellow to a very faint red aafter the addition of 29.5ml.
A) How many moles of hydroxide ion are neutralized in the analysis? 2.15 x 10-3 mol
B.) What is the molar concentration of the hydroxide ion in the saturated solution? 0.0861 M
C.) What is the molar solubility of strontium hydroxide? 0.0431 M
D. What is the solubility product, Ksp, for strontium hydroxide? 3.20 x 10-4
E) For the determination of the Ksp for strontium hydroxide, the stoichiometric point (as determined by the endpoint of methyl orange indicator) should not be surpassed. Suppose the stoichiometric point in an experiment is surpassed (i.e., surpassing the faint red of the indicator). Will the reported solubility product of strontium hydroxide be too high, too low, or unaffected? Explain.
A saturated solution of hydroxide is prepared and the excess solid strontium hydroxide is allowed to settle. A 25.0-mL aliquot of the satuared solution is withdrawn and transferred to an erlenmeyer flask, and two drops of methyl orange indicator are added. A 0.073 M HCL solution (titrant) is dispensed from a buret into the solution ( analyte). The solution turns from yellow to a very faint red aafter the addition of 29.5ml.
A) How many moles of hydroxide ion are neutralized in the analysis? 2.15 x 10-3 mol
B.) What is the molar concentration of the hydroxide ion in the saturated solution? 0.0861 M
C.) What is the molar solubility of strontium hydroxide? 0.0431 M
D. What is the solubility product, Ksp, for strontium hydroxide? 3.20 x 10-4
E) For the determination of the Ksp for strontium hydroxide, the stoichiometric point (as determined by the endpoint of methyl orange indicator) should not be surpassed. Suppose the stoichiometric point in an experiment is surpassed (i.e., surpassing the faint red of the indicator). Will the reported solubility product of strontium hydroxide be too high, too low, or unaffected? Explain.
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A) How many moles of hydroxide ion are neutralized in the analysis? 2.15 x 10-3 mol
The moles of hydroxide is equal to the moles of HCl = 2.15 x 10^-3 mol = (V in L)(M) This confirms your reported number.
B.) What is the molar concentration of the hydroxide ion in the saturated solution? 0.0861 M
molar concentration = moles OH^-/L of solution = (2.15 x 10^-3 mole)/(0.0250 L) = 0.0861 mole/L This confirms your reported number.
C.) What is the molar solubility of strontium hydroxide? 0.0431 M
molar solubility of Sr(OH)2 = [Sr^2+] = [OH^-]/2 = (0.08614 M)/2 = 0.04307 M = [Sr^2+] This confirms your reported number.
D. What is the solubility product, Ksp, for strontium hydroxide? 3.20 x 10-4
Sr(OH)2(s) <=> Sr^2+(aq) + 2 OH^-(aq)
Ksp = [Sr^2+][OH^-]^2 = (0.0431)(0.0861)^2 = 3.19 x 10^-4 = 0.000319
Since you didn't ask I won't go into E). Bet you can do it.
Hope this is helpful to you. JIL HIR
The moles of hydroxide is equal to the moles of HCl = 2.15 x 10^-3 mol = (V in L)(M) This confirms your reported number.
B.) What is the molar concentration of the hydroxide ion in the saturated solution? 0.0861 M
molar concentration = moles OH^-/L of solution = (2.15 x 10^-3 mole)/(0.0250 L) = 0.0861 mole/L This confirms your reported number.
C.) What is the molar solubility of strontium hydroxide? 0.0431 M
molar solubility of Sr(OH)2 = [Sr^2+] = [OH^-]/2 = (0.08614 M)/2 = 0.04307 M = [Sr^2+] This confirms your reported number.
D. What is the solubility product, Ksp, for strontium hydroxide? 3.20 x 10-4
Sr(OH)2(s) <=> Sr^2+(aq) + 2 OH^-(aq)
Ksp = [Sr^2+][OH^-]^2 = (0.0431)(0.0861)^2 = 3.19 x 10^-4 = 0.000319
Since you didn't ask I won't go into E). Bet you can do it.
Hope this is helpful to you. JIL HIR