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I was going over Gchem chapter 9 p.285 on Kaplan blue book.
The answer for the second question says
1.36x10^-2 mol of PbBr2 is dissolved in 1L of solution, so the concentration of solution 1.36 x 10^-2 M. Since this is higher than the concentration of a saturated solution, this solution would be supersaturated.
I understand that 1.36x10^-2 mol is dissolved in 1L, but
the concentration of a saturated solution is
8.07 x 10^-3 + (1.61 x 10^-2) = 2.42 x 10^-3.
2.42 x 10^-3 is smaller than 1.36 x 10^-2
so I don't know why the solution says 1.36x10^-2 is higher than the concentration of a saturated solution. Shouldn't it be less?
Just in case if some of you wanna know what the question was, here it goes
"what are the concentrations of each of the ions in a saturated solution of PbBr2, given that the Ksp of PbBr2 is 2.1 x 10^-6?
If 5g of PbBr2 are dissolved in water to make 1L of solution at 25 celcius, would the solution be saturated, unsaturated, or supersaturated?"
the answer =
concentration of Pb in a saturated solution = 8.07 x 10^-3M
concentration of Br is 1.61 x 10^-2.M
5g of PbBr2 = 1.36x 10^-2 mol in 1 L thus 1.36 x 10^-2 M
and it says it is supersaturated because 1.36x10^-2M is higher than the concentration of saturated solution and I don't think that makes sense.
The answer for the second question says
1.36x10^-2 mol of PbBr2 is dissolved in 1L of solution, so the concentration of solution 1.36 x 10^-2 M. Since this is higher than the concentration of a saturated solution, this solution would be supersaturated.
I understand that 1.36x10^-2 mol is dissolved in 1L, but
the concentration of a saturated solution is
8.07 x 10^-3 + (1.61 x 10^-2) = 2.42 x 10^-3.
2.42 x 10^-3 is smaller than 1.36 x 10^-2
so I don't know why the solution says 1.36x10^-2 is higher than the concentration of a saturated solution. Shouldn't it be less?
Just in case if some of you wanna know what the question was, here it goes
"what are the concentrations of each of the ions in a saturated solution of PbBr2, given that the Ksp of PbBr2 is 2.1 x 10^-6?
If 5g of PbBr2 are dissolved in water to make 1L of solution at 25 celcius, would the solution be saturated, unsaturated, or supersaturated?"
the answer =
concentration of Pb in a saturated solution = 8.07 x 10^-3M
concentration of Br is 1.61 x 10^-2.M
5g of PbBr2 = 1.36x 10^-2 mol in 1 L thus 1.36 x 10^-2 M
and it says it is supersaturated because 1.36x10^-2M is higher than the concentration of saturated solution and I don't think that makes sense.
