Give reasons for the following statements:

1. If fractional distillation is carried out using a liquid-liquid mixture, one liquid will remain in the flask & the other will be collected in the receiver.

2. Evaporation of a common salt solution or sea water, leaves behind common salt inside the evaporating dish after heating.

3. Components in a mixture are present in varying proportions and not in a fixed proportion.

4. Gunpowder is an example of a heterogeneous mixture.

5. In chromatography the absorbent medium e.g. Whatman filter paper is known as the - stationary phase.

1. Fractional distillation separates two miscible liquids with different boiling points. The fractionating column traps and condenses the higher boiling point component, allowing only the lower boiling point component to enter the condenser and be collected.

2. During evaporation of common salt solution or sea water, common salt is left behind inside the evaporating dish on heating because water, i.e., the liquid component is lost to the atmosphere as it gets converted into water vapour.

3. Mixture is an impure substance formed by mixing two or more elements or compounds in any proportion. Mixtures do not have a definite set of properties. If the components are mixed in a fixed proportion then it will form a compound and not a mixture.

4. Gunpowder is considered as a heterogeneous mixture because its components charcoal, sulphur, and potassium nitrate are not uniformly mixed throughout, and it has different properties and composition throughout the mixture.

5. In chromatography the absorbent medium e.g., Whatman filter paper is known as the stationary phase because the filter paper made up of cellulose binds the water tightly to the paper whereas in mobile phase, the solvent or the solution moves due to capillary action.