Asked by Jhanvi
Determine the concentrations of K2SO4, K , and SO42– in a solution prepared by dissolving 2.84 × 10–4 g K2SO4 in 2.25 L of water. Express all three concentrations in molarity. Additionally, express the concentrations of the ionic species in parts per million (ppm). Note: Determine the formal concentration of SO42–. Ignore any reactions with water.
Answers
Answered by
DrBob222
2.84-4g/about 175 = about 1.62E-6
and 1.62E-6/2.25 = 7.2E-7 M
.......K2SO4 ==> 2K^+ + SO4^2-
I......7.2E-7M....0......0
C.....-7.2E-7..2*7.2E-7M..7.2E-7M
E.......you can fill this in.
The easy way to convert to ppm is to calculate the number of mg/L. For example, for 7.2E-7 (sulfate):
g SO4 = 7.2E-7 mol/L x (96 g/mol) = 6.9E-5 g/L and that is 6.9E-2 mg/L = 0.069 ppm.
Check my work.
and 1.62E-6/2.25 = 7.2E-7 M
.......K2SO4 ==> 2K^+ + SO4^2-
I......7.2E-7M....0......0
C.....-7.2E-7..2*7.2E-7M..7.2E-7M
E.......you can fill this in.
The easy way to convert to ppm is to calculate the number of mg/L. For example, for 7.2E-7 (sulfate):
g SO4 = 7.2E-7 mol/L x (96 g/mol) = 6.9E-5 g/L and that is 6.9E-2 mg/L = 0.069 ppm.
Check my work.
Answered by
Jhanvi
I don't understand
Answered by
DrBob222
You need to do better than that. You have a page and a half of work and you don't understand. That doesn't tell me anything. I have to know where to start. What don't you understand. Exactly and detailed.
Answered by
Jhanvi
I don't understand it at all from the beginning. I get that you divided moles by molar mass for the first thing but I don't know what you did after that. And would I do the same for the rest of the question as well? K2SO4, K+, SO4..I think it would help me if you could do just a part of the problem step by step. I do however understand how I can convert to ppm so thank you for that!
Answered by
DrBob222
Perhaps I just put in too much stuff. K2SO4 is an ionic compound and it dissolves in water to produce 2K^+ and SO4^2-. If the molarity of K2SO4 is 7.2E-7 M, then that must be the concn of the SO4^2- and twice that must be the concn of the K^+ (since there are 2 K^+ per molecule K2sO4. I just put all of that information in the form of an ICE chart.
Answered by
Jhanvi
Thank you so much! I understand it now! I don't know what the ICE chart is so I didn't know what you were doing. But thank you!
Answered by
DrBob222
I like the ICE chart and I learned to make ICE charts by volunteering to do this homework help. The I stands for initial, the C for change, and the E for equilibrium. It is a very good way to sum up a problem with initial, change, and equilibrium, and many teachers around the country are using this technique.
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.