# The pH of 0.04M hydrazine solution is 9.7.Calculate ionization constant kb and PKb.

1
by Raksha1

## Answers

The Brainliest Answer!
2016-02-09T11:32:43+05:30

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.

NH2NH2 + H2O -----> NH2NH3+ + OH-

From   the  given pH   the Hion concentration can be measured.

So, we have
[H+] = antilog (–pH) = antilog (–9.7) = 1.67 × 10^-10
Now, [OH-]  = Kw / [H+] = 1 × 10^-14/ 1.67 × 10^-10                         = 5.98 × 10^-5//

The concentration of the corresponding hydrazine ion is also the same as that of hydroxyl ion. The concentration of both these ions is very small so the concentration of the undissociated base can be taken equal to 0.004 M

Thus, Kb= [NH2NH3+][OH-] / [NH2NH2]= (5.98 × 10^-5)^2/ 0.004 = 8.96 × 10^-7//

So, pKb = –logKb = –log(8.96 × 10–7) = 6.04//

Hope it helped ^_^