A mixture of acetone and toluene was distilled in a distillation flask. On slow heating it was found that temperature became constant at 56°C for some time and the residual liquid left was toluene. When the heating was continued, again the temperate became constant at 80°C.

Answer the following questions.

(a) What is the boiling point of acetone and toluene ?

(b) Why was it possible to separate acetone from toluene ?

(c) Why does temperature remain constant for some time at 56°C even though heating was continued.

Write the steps you would use for making tea. Use the words—solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).

Pragya makes a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would she observe as the solution cools? Explain.

Find the solubility of each salt at 293 K. Which salt has the highest solubility at this temperature?

Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).

Explain the following giving examples:

Saturated solution

Explain the following giving examples:

Pure substance

Explain the following giving examples:


Colloid