× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
G
4
K
3
m
2
c
2
r
2
p
2
s
2
s
2
b
2
c
2
R
2
c
2
Home Q & A Board Science-Related Homework Help Chemistry (Moderator: Laser_3)
New Topic  
smokeyd smokeyd
wrote...
Posts: 111
Rep: 0 0
11 years ago
Dihydrogen phosphate H2PO4^- , has an acid dissociation constant of 6.2 x 10^-7. What is the conjugate base of H2PO4^- and what is its base dissociation constant?

A. H3PO4 , 1.6 x 10^6
B. H3PO4 , 1.6 x 10^-8
C. HPO4^2- , 1.6 x 10^6
D. HPO4^2- , 1.6 x 10^-8
Read 433 times
1 Reply

Related Topics

Replies
spa
wrote...
#1
11 years ago
Dihydrogen phosphate behaves as a Bronsted-Lowry acid in the following way:

H2PO4^- + H2O <-> HPO4^-2 + H3O^+

H2PO4^- is the acid, HPO4^-2 is the conjugate base.

To find Kb, use the relationship Ka x Kb = Kw.

Kw/Ka = Kb
 Kb = (10^-14) / (6.2x10^-7) = 1.61x10^-8

So, the correct answer is D.
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  1241 People Browsing
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Live Chat
Related Images
  
 423
  
 290
  
 85
Your Opinion
Who will win the 2024 president election?
Votes: 10
Closes: November 4
Previous poll results: Which 'study break' activity do you find most distracting?