Homework Help: CHEMISTRY FOR DR. BOB or anyone else

Posted by Delli on Friday, May 11, 2007 at 12:39pm.

A hypothetical weak acid HA, was combined with NaOH in the following proportions: 0.20 mol HA, 0.08 mol NaOH. The mixture was then diluted to a total volume of 1L, and the pH measured.

(a) If pH=4.80, what is the pKa of the acid

(b) how many additional moles of NaOH should be added to the solution to increase the pH to 5.00

Duplicate post. answered the original.

Sorry bout that. I didn't notice part b.
Assuming not all of the HA is neutralized and that you still have a buffered solution,
Use the Henderson-Hasselbalch equation.
pH = pKa + log [(base)/(acid)].
OR just use the simple Ka expression you used for part a, plug in (H^+) equivalent to pH = 5.00.

No one has answered this question yet.

Answer this Question

Related Questions

CHEMISTRY FOR DR. BOB or anyone else - A hypothetical weak acid HA, was combined...
FOR DR. BOB - With regards to my last question about the acid. Just to clarify, ...
Introductory Chemistry - In a titration 25.1ml of a monoprotic weak acid is ...
chemistry - titration - Show that for the titration of a weak acid, HA, with ...
Chemistry - I keep getting the last part of this question wrong. Strong base is ...
CHEMISTRY - 7. At pH 7.4 a weak organic acid with a pKa of 6.4 would be 60% ...
Chemistry - An unknown monoprotic weak acid, HA, has a molar mass of 65.0. A ...
Chemistry/pH- Weak Acid - Hi again! I have a new question, Can you help me? ...
Chemistry - A 0.100 mol quantity of a monoprotic acid HA is added to 1.00 L of ...
Chemistry - You want to make 1000 ml of an 0.1 M HA buffer so that the pH=pKa of...

For Further Reading

First Name:
School Subject:
Answer: