December 08, 2022, 06:47:04 AM
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### Topic: Reason between protonated and deprotonated bases  (Read 899 times)

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#### liravsc

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##### Reason between protonated and deprotonated bases
« on: November 16, 2021, 06:40:23 PM »
"An acid with a pKa of 8 is present in a solution of pH 6. What's the reason between the protonated and deprotonated bases?"

I'm probably completely wrong, but I tried Handerson-Hasselbach's equation here. Got stuck at $$\frac {log[A-]}{log[HA]} = -2$$. I can't think of anything else how to calculate this. Thank you!
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#### Borek

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##### Re: Reason between protonated and deprotonated bases
« Reply #1 on: November 17, 2021, 02:55:43 AM »
Reason or ratio?

But yes, HH equation is the way to go.
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#### sjb

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##### Re: Reason between protonated and deprotonated bases
« Reply #2 on: November 17, 2021, 03:18:32 AM »
More like $$log \frac {[A-]}{[HA]} = -2$$

Can you find another equation relating [A-] and [HA]?

#### liravsc

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##### Re: Reason between protonated and deprotonated bases
« Reply #3 on: November 17, 2021, 08:29:50 AM »
Reason or ratio?

But yes, HH equation is the way to go.

haha ratio! Sorry I'm translating from portuguese

EDIT: figured it out, since the difference between the pH and pKa is -2, the ratio is 10-2. Is that correct?
« Last Edit: November 17, 2021, 09:31:03 AM by liravsc »
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