(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Estimate the Ka the using the assumption that the color change can be seen by our eyes when [ln-]/[Hln] = 1/10

to see the acid form or [ln-]/[Hln] = 10/1 to see the color associated with the base.

Use these numbers with your measured [H+] to calculate a Ka for each indicator you measured.

2. Relevant equations

acid-base base-acid H+

Phenolphthalein 8.7 7.4 8.91E-09

I got the hydronium concentration by taking taking the average of the ph values and doing 10^-ph. How do i get the ka estimates?

Do i set up the equation like this: ka = 1/[H+] or something like this?

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# Homework Help: Ka estimate

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