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$2 Chomiatry = I, , Example 2.7 (Intext Question 2.5), Calculate the molality, molarity and mole fraction of KL in a 20% (m/m) aqueous soluti, of potassium iodide. Density of the solution = 1,202 g mL", ,, , Solution, Let the mass of solution be 100 g, , Mass of KI = 20g, , .. Mass of solvent = 100 —20 = 80 g, Molar mass of KI = 39 + 127 a 166, (i) Calculation of molality (m), , Number of moles of KI = a = 0.12, , : . 0., * Molaty= 212100 5,, , (ii) Calculation of molarity (M), Density of the solution = 1.202 g mL"!, , , , + Volume of 100g solution = 10. — 3.2 mr, , 0.12 x 1000, ass 1.45 M, , (iii) Calculation of mole function, , -. Molarity =, , 20/8, , Number of moles of water in 100g solution =, , , , teins