Ka/Kb of 10^-4

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Parker Smith
Posts: 102
Joined: Thu Jul 25, 2019 12:15 am

Ka/Kb of 10^-4

Postby Parker Smith » Thu Jan 16, 2020 2:54 pm

I know Dr. Lavelle said to be careful with K values of 10^-4 and using the assumption rule. When is it "safer" to use the assumption rule for values of K equal to 10^-4?

KBELTRAMI_1E
Posts: 108
Joined: Sat Jul 20, 2019 12:17 am

Re: Ka/Kb of 10^-4

Postby KBELTRAMI_1E » Thu Jan 16, 2020 3:00 pm

It's not "safe" when the value is like 8.5555x10^-4 because that's too close to 10^-3. if its 2.57584 x10^-4 you should be good. he said they would make it obvious on the test though.

805307623
Posts: 99
Joined: Fri Aug 09, 2019 12:17 am

Re: Ka/Kb of 10^-4

Postby 805307623 » Thu Jan 16, 2020 3:00 pm

I would say not to use the assumption for 10^-4, just to be safe.

DanielTalebzadehShoushtari2A
Posts: 53
Joined: Fri Aug 02, 2019 12:16 am

Re: Ka/Kb of 10^-4

Postby DanielTalebzadehShoushtari2A » Thu Jan 16, 2020 3:11 pm

You can use the assumption to calculate x, and then check to see if x is less than 5% of the original concentration. If it is, then the assumption is valid.


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