Homework error?

[sarahtang4B]

On problem 6A19 part c of 7th edition, the solutions manual says the concentration given is 3.1e-3 when the textbook gives the concentration as just 3.1 mol per liter.

Which concentration do we use? am I just missing a step in solving??

[Sarah Zhao 4C]

I would use whichever one gets you to the answer in the solution manual. You made need to do the problem with both concentrations to determine if it was a typo or if they used the 10^-3 number throughout the whole problem.

[abbydouglas1K]

I'm glad I'm not the only one who thought this because if you do divide Kw by 3.1 mol/l you get a concentration with a value of 10^-15 which I'm not sure is possible