Question

calculate the degree of ionisation and ph of .05 M solution of a weak base having the ionization constant kb is 1.77 *10-5.also calculate the ionization constant of the conjugate acid of this base answer=degree of dissociation-1.88*10^-2ph=10.96 ka=5.64 *10^-10

Answer 1

To calculate the degree of dissociation, you need to first write down what yoiu are given as this will enable you to have easier manipulation.

Concentration= 0.05 M

Ionization constant, kb= 1.77 x 10⁻⁵

Then the formula for kb= C∝²

where C is the concentration and ∝ degree of ionization.

therefore ∝ =√ 1.77 x 10⁻⁵ /0.05

                 ∝= 0.0188

To calculate pH first you need to get the equilibrium concentration

= C∝

0.05 x 0.0188

= 9.4 x 10⁻⁴ M

pOH = -log  9.4 x 10⁻⁴

        = 3.0

therefore pH= 14 - 3

                pH= 11.0.