Question

What do you mean by normality and molarity of a solution? How are these related?

Answer 1

Molar Concentration: It is defined as the amount of substance per unit volume of solution.
Solute: The compound which is mixed in a given substance, is known as solute.
Solvent: The compound which is given and in which solute is mixed, is known as solvent.

Complete step by step solution:
First of all we will read about the concentration terms.
Solute: The compound which is mixed in a given substance, is known as solute.
Solvent: The compound which is given and in which solute is mixed, is known as solvent.
Molar Concentration: It is defined as the amount of substance per unit volume of solution.
Molarity: It is defined as the number of moles in the given volume of the solution. The unit of the molarity is as: $mol/litre$.
Molality: It is defined as the number of moles of solute per kilogram of solvent. The unit of molality is: $mol/kg$.
Normality: It is defined as the gram equivalent weight per unit litre of solution. The unit of normality is: $eq/litre$.
Equivalent mass: It is defined as the mass of one equivalent.
Ppm (parts per million): It is also expressed in milligrams per litre. It is defined as mass of substance per unit volume of water.
To calculate the relation between molarity and normality we first know the term n-factor.
n-factor: It is defined as the number of hydrogen ions replaced by one mole of an acid or number of hydroxide ions replaced by one mole of base, is known as n-factor. For example: the n-factor of sulphuric acid is two because it can replace two hydrogen ions from the solution of sulphuric acid. And similarly the n-factor of sodium hydroxide is one because from the solution of one mole of sodium hydroxide one hydroxide ion can be replaced.
So if we want the relation between molarity and normality it is as follows:

Normality is equal to the product of molarity and its n-factor.

Note: Number of moles: It is defined as the ratio of mass of substance or molecule in the given solution to the molar mass of that substance or molecule in the solution.
Mole fraction: It is defined as the ratio of number of moles of the solute or solvent to the total number of moles in the solution.