e Chemistry question I che x y se Alaberma State Universit X

e Chemistry question I che x y se Alaberma State Universit XG ammonia Ph-Google sx \\ M Inbox (61) New Tab d www.saplinglearning.com/ibiscms/mod/ibis/view.php?id=4589194 C Q Sapling Learning macmilan learming ::: Apps Scholarship Award fc Scholarship Opportu \"Hit the Books\" Scho 6 3100 Due Date: Points Possible: Grade Category: 2/26/2018 11:59 PM 100 Quiz 3 Map Sapling Learning Enough of a monoprotic acid is dissolved in water to produce a 0.0109 M solution. The pH of the resulting solution is 2.30. Calculate the K for the acid. Number Policies: Quiz 10 You can check your answers. You can view solutions after the due date. You have three attempts per question There is no penalty for incorrect answers. 12 1 13 1 eTextbook 14 Help With This Topic 15 1 16 1 17 0 18 1 19 0 20 0 Web Help& videos D Technical Support and Bug Reports Previous Check Answer Next Exit Hint 2011-2018 Sapling Learning, Inc about uscrsprivacy policy erms of usecotus help O Type here to search 05 PM 2/26/2018

Solution

use:
pH = -log [H+]
2.3 = -log [H+]
[H+] = 5.012*10^-3 M
HA dissociates as:

HA          ----->     H+   + A-
1.09*10^-2                 0         0
1.09*10^-2-x               x         x


Ka = [H+][A-]/[HA]
Ka = x*x/(c-x)
Ka = 5.012*10^-3*5.012*10^-3/(0.0109-5.012*10^-3)
Ka = 4.27*10^-3
Answer: 4.27*10^-3