Question

The enthalpy of neautralization of a weak monoprotic acid $\left(HA\right)$ in $1M$ solution with a strong monoacidic base is $-55.95kJ/mol$. If the unionized acid requires $1.4kJ/mol$ heat for its complete ionization and enthalpy of neutralization of the strong monobasic acid with a strong monoacidic base is $-57.3kJ/mol$. What is the percentage ionization of the weak acid in molar solution? (Put your answer upto two decimal points)

Answer 1

Given, the enthalpy of neutralization of the strong monobasic acid with a strong monoacidic base is $-57.3kJ/mol$

Again, the enthalpy of neautralization of a weak monoprotic acid with a strong monoacidic base is $-55.95kJ/mol$.

So the energy used for diisociation of week acid is $(57.3-55.95)kJ/mol=1.35kJ/mol$

But, the heat required for complete ionization of weak monobasic acid is $1.4kJ/mol$

So the percentage ionization of the weak acid $=\frac{1.4-1.35}{1.4}\times 100=3.571\%$