Question

(6) 24. Draw the rough titration curve of 20.0mL of 0.100M acetic acid (Ka = 1.8 x 10-5) being titrated with 0.100M NaOH. Cal

0 0
Add a comment Improve this question Transcribed image text
Answer #1

pKa of acetic acid = -log 1.8x10-5 = 4.75

CH3COOH + HCl -------------------------> CH3COONa + H2O
20x0.1 0 0 ---- initial mmoles

I) initial pH

pH of acid = 1/2[pKa -log C] = 1/2[4.75 -log 0.1]

=2.875

II)pKa = 4.75

CH3COOH + HCl -------------------------> CH3COONa + H2O
20x0.1=2 0 0 ---- initial mmoles

1.5 0 0.5 ------ at 1/4 equivalence

pH of this buffer = pKa +log [conjugate base]/[acid] Hendersen equatio

= 4.75 + log 0.5/1.5

= 4.27

CH3COOH + HCl -------------------------> CH3COONa + H2O
20x0.1=2 0 0 ---- initial mmoles

0.5 0 1.5 ------ at 3/4 equivalence

pH of this buffer = pKa +log [conjugate base]/[acid] Hendersen equatio

= 4.75 + log 1.5/0.5

= 5.227

III)

At equivalence

CH3COOH + HCl -------------------------> CH3COONa + H2O
20x0.1=2 0 0 ---- initial mmoles

0 0 2 ------ at equivalence

[salt] formed = mmoles/ total volume = 2 /(20+20) = 0.05 M

pH of salt solution of strong base and weak acid = 1/2[pKw + pKa + log C]

= 1/2[14 + 4.75 + log 0.05] = 8.7244

ey 822 8724 5.22 5 10 15 20 25 Vol of Naolt

Add a comment
Know the answer?
Add Answer to:
(6) 24. Draw the rough titration curve of 20.0mL of 0.100M acetic acid (Ka = 1.8...
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