Define the following terms:

(i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.

(i) Mole fraction - The mole fraction of a particular component in a solution is the ratio of the number of moles of that component to the total number of moles of all the components present in the solution.

Mathematically,

Mole Fraction of component

Mole Fraction is independent of temperature.

(ii) Molality - Molality of a solution is defined as the number of moles of solute dissolved per 1000g [1kg] of the solvent. It is represented by m.

Molality actually represents the concentration of solution in mol / kg.

Mathematically,

Molality

It is represented by m.

(iii) Molarity- The number of moles of solute dissolved per litre of the solution at a particular temperature is called the molarity of the solution at that temperature.

Molarity actually represents the concentration of a solution in mol / L.

Mathematically,

Molarity

(iv) Mass percentage - Mass percentage is defined as the mass of the solute in grams dissolved per 100g of the solution. It is also referred to as weight percentage [w/w].

For example, 10% [by mass] urea solution means that 10 g of urea are present in 100 g of solution, the solvent being only 100-10 = 90 g.

Mathematically, the mass percentage of a solute in a solution is given by:

Mass Percentage of Solute

Or

Mass Percentage of Solute