A community for students.
Here's the question you clicked on:
 0 viewing
vera_ewing
 one year ago
Given that the pKa of acetic acid is 4.8, what would be the likely result of adding 1 mL of 0.1 M HCl to a 0.1 M acetate buffer at a pH of 5.0?
A. The pH would drop slightly.
B. The pH would increase significantly.
C. The pH would drop significantly.
D. The pH would increase slightly.
vera_ewing
 one year ago
Given that the pKa of acetic acid is 4.8, what would be the likely result of adding 1 mL of 0.1 M HCl to a 0.1 M acetate buffer at a pH of 5.0? A. The pH would drop slightly. B. The pH would increase significantly. C. The pH would drop significantly. D. The pH would increase slightly.

This Question is Closed

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0Well I feel like it might D maybe?

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0why did you choose that?

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0Since the pKa is 4.8

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0Actually, I think it's A

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0OK now a little bit closer, If you add an acid to a buffer always the pH is going to drop. If you add a base the pH will increase. How do you know if the pH is dropping slightly or significantly?

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0It would drop significantly, since the pKa is 4.8?

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0The pKa is not going to tell you if the pH is going to drop slightly or significantly. The buffer capacity and the concentration of the buffer and the amount of acid that you add is going to tell you if the pH change slightly or significantly

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0Ohh okay! So the answer is C?

Rushwr
 one year ago
Best ResponseYou've already chosen the best response.0Shouldnt it be A? @Cuanchi Can u explain it a little more?

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0the problem is giving you two very similar options A and C, how can you figure out which one is the correct answer?

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0you have the HendersonHasselbalch Equation pH = pKa + log ([base]/[acid]) when the problem said that the concentration of the buffer is 0.1M that means that the concentration of the base/acid = 1 (both are 0.1M) an then the log 1 = 0 then the pH of the buffer is equal to the pKa. when you add HCl to the buffer, the HCl is reacting with the sodium acetate , and produce more acetic acid and decrease the concentration of sodium acetate in the buffer. At this point the relationship [base]/[acid] is <1 then the log of a number <1 is negative and in the equation the pH is going to be lower than the pKa

Rushwr
 one year ago
Best ResponseYou've already chosen the best response.0I thought it in this way: since its an acid there should be a slight drop in pH as its concentration is small

vera_ewing
 one year ago
Best ResponseYou've already chosen the best response.0@Cuanchi Is it C then?

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0Your idea @Rushwr is correct the only thing you have to be sure that the amount of strong acid (moles) is lower than the amount of salt that you have in your buffer. If the amount of strong acid is bigger than the amount of salt you don't have buffer anymore and you have just acid and NaCl

cuanchi
 one year ago
Best ResponseYou've already chosen the best response.0I will go for A because the problem doesn't mention the volume of the buffer that you have

Rushwr
 one year ago
Best ResponseYou've already chosen the best response.0yey my answer is correct ! @Cuanchi Thank you
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.