Factors Affecting Degree of Ionization | NEB |

There are different factors that affect the degree of ionization

1. Nature of Electrolyte
2. Nature of Solvent
3. Temperature
4. Dilution

Nature of Electrolyte :

The value of alpha depends upon the nature of electrolytes.

Strong electrolytes like NaCl, KCl, Na₂SO₄, etc have higher values of α found to be nearly equal to 1.

The strong electrolyte is almost completely ionized at a reasonable concentration.

Similarly, for weak electrolytes like CH₃COOH, NH₄OH, etc the value of α is always far less than 1

The weak electrolyte is partially ionized even in a diluted solution.

Nature of Solvent :

The value of α depends directly on the ionizing power of the solvent.

The ionizing power which in turn depends upon the dielectric constant value of the solvent.

Water has the highest dielectric constant value found to be 80 at 25 ⁰ C.

So it is an excellent ionizing solvent.

The greater the dielectric constant value of solvent, the greater will be its ionizing power and greater will be the value of α.

 Temperature :

The value of α depends upon temperature.

When the temperature is raised then the intermolecular as well as an interatomic force of attraction among the molecules and ions weaken and finally cleave and the value of α increases.

Dilution :

The value of α increases with increases in dilution.

When the solution is diluted the ionization process increases and at infinite dilution, the value of α becomes maximum which is found to be 1.