Question

4. Briefly explain the meaning of the term buffer capacity. A formic acid/sodium formate solution would be expected to buffe
0 0
Add a comment Improve this question Transcribed image text
Answer #1

4. Buffer capacity is defined as the ration of number of moles of acid [H+] or base [OH-] added per 1 liter of the solution to the change in pH of the solutionp.

the effective buffer capacity is from pka-1 to pka+1

and the pKa formic acid , the effective buffer capacity is 2.74 to 4.74( pKa of formic acid is 3.74)

A solution of formic/sodium acetate is expected to act as buffer between the pH range 2.74 to 4.74(

5. The pOH of basic buffer is given pOH = pkb + log(C5H5NHBr/C5H5N)

   pKb of C5H5N = -logKb = -log(1.40*10^-9) = 8.85

   [C5H5N] = 3.48 M

   [C5H5NHBr] = 2.52 M

   pOH = 8.85 + log(2.52/3.48)= 8.71  

====> pH = 5.29

6.

after addition of NaOH

poH of buffer = pkb + log((C5H5NHBr+HCl)/(C5H5N-HCl))

pOH = 8.85+log((2.205+0.474)/(3.045-0.474) = 8.86

pH = 5.14

Add a comment
Know the answer?
Add Answer to:
4. Briefly explain the meaning of the term buffer capacity". A formic acid/sodium formate solution would...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT