Equilibrium Question 307
Question: What is the pH of 0.01 M glycine solution’ For glycine, $ Ka_1=4.5\times {10^{-3}} $ and $ Ka_2=1.7\times {10^{-10}} $ at 298 K [AIIMS 2004]
Options:
A) 3.0
B) 10.0
C) 6.1
D) 7.2
Show Answer
Answer:
Correct Answer: C
Solution:
$ K=Ka_1\times Ka_2 $
$ =4.5\times {10^{-3}}\times 1.7\times 10^{10} $
$ {H^{+}}=\sqrt{Kc} $
$ =\sqrt{4.5\times {10^{-3}}\times 1.7\times {10^{-10}}\times .01} $
$ =.87\times {10^{-7}} $
$ pH=-\log \ 0.87\times {10^{-7}} $
$ =7-0.93=6.07 $ .
