# Chemistry Class 11 NCERT Solutions: Chapter 7 Equilibrium Part 13

Q: 40. Classify the following species into Lewis acids and Lewis bases and show how these act as Lewis acid/base:

(A)

(B)

(C)

(D)

Answer:

(A) is a Lewis base since it can donate its lone pair of electrons

(B) is a Lewis base since it can donate a pair of electrons

(C) is a Lewis acid since it can accept a pair of electrons’

(D) is a Lewis acid since it can accept a pair of electrons

Q: 41. The concentration of hydrogen ion in a sample of soft drink is. What is its?

Answer: Given,

Value of soft drink

Q: 42. The pH of a sample of vinegar is 3.76. Calculate the concentration of hydrogen ion in it.

Answer:

Given,

It is known that,

Hence, the concentration of hydrogen ion in the given sample of vinegar is M.

Q: 43. The ionization constant of and respectively. Calculate the ionization constants of the corresponding conjugate base.

Answer:

It is known that,

Given,

Hence, of its conjugate base

Given,

Hence, of its conjugate base

Given,

Hence, of its conjugate base