Question Help

[epherbertson]

Hi
I have been struggling with this one for a while (probably super easy). Any help is appreciated



Thanks

[kiwiberry]

Hi
I have been struggling with this one for a while (probably super easy). Any help is appreciated

(Image removed from quote.)

Thanks

We know that m(PbCl₂) = 0.595 g
Therefore n(PbCl₂) = 0.595 / (207.2+2*35.45) = 0.21395... mol
n(PbCl₂):n(Pb²⁺) = 1:1
So n(Pb²⁺) = 0.21395... mol
m(Pb²⁺) = 0.21395...*207.2 = 0.44330... g
c(Pb²⁺) = 0.44330... / 0.05 = 8.866... g/L
So the answer is A!

[epherbertson]

Thank you so much
I literally did that exact same working, must have just put the numbers in my calculator wrong.
Thanks heaps

[mylinh-nguyen]

We know that m(PbCl₂) = 0.595 g
Therefore n(PbCl₂) = 0.595 / (207.2+2*35.45) = 0.21395... mol
n(PbCl₂):n(Pb²⁺) = 1:1
So n(Pb²⁺) = 0.21395... mol
m(Pb²⁺) = 0.21395...*207.2 = 0.44330... g
c(Pb²⁺) = 0.44330... / 0.05 = 8.866... g/L
So the answer is A!

quick question if this is ever seen, why do you divide mass over volume when finding conc of lead
m(Pb2+) = 0.21395...*207.2 = 0.44330... g
c(Pb2+) = 0.44330... / 0.05 = 8.866... g/L

[kiwiberry]

quick question if this is ever seen, why do you divide mass over volume when finding conc of lead
m(Pb2+) = 0.21395...*207.2 = 0.44330... g
c(Pb2+) = 0.44330... / 0.05 = 8.866... g/L

Here you need to find the concentration in g/L, so you divide mass by volume. If you wanted to find it in mol/L, then you would use the formula c=n/v

[mylinh-nguyen]

Here you need to find the concentration in g/L, so you divide mass by volume. If you wanted to find it in mol/L, then you would use the formula c=n/v

OH ok thank you!!!