NTA Abhyas NEET2020ChemistryIonic EquilibriumPractice
Which of the following would cause the percent ionization of a week acid to increase?
Options
- AAddition of a strong acid
- BAddition of a salt containing its conjugate base
- CDiluting with more water
- DThe percent ionization of a week acid is a constant and cannot be increased.
Correct answer
C. Diluting with more water
Step-by-step solution
K a = C α 2 1 - α . If α < 5 % , then 1 - α = 1 So K a = C α 2 or α = K a C This shows that degree of ionization is inversely proportional to the square root of its molar concentration. Hence, α increases when solution is diluted with water.