Consider the following aqueous solutions. I. 2.2 g Glucose in 125 mL of solution. II. 1.9 g Calcium chloride in 250 mL of solution. III. 9.0 g Urea in 500 mL of solution. IV. 20.5 g Aluminium sulphate in 750 mL of solution. The correct increasing order of boiling point of these solutions will be : [Given : Molar mass in g mol ^ -1 : H =1, C =12, ~N =14, O =16, Cl =35.5, Ca =40, Al =27 and S =32]
B. I < II < III < IV
T_b = i k_b m For dilute solution (M = m) Molarity i m (I) M_ glucose = 2.2 180 1000 125 = 0.098 0.098 1 (II) M_ CaCl_2 = 1.9 111 1000 250 = 0.068 0.068 3 (III) M_ urea = 9 60 1000 500 = 0.3 0.3 1 (IV) M_ Al_2(SO_4)_2 = 20.5 342 1000 750 0.08 0.08 5 Order of T_b = Al_2(SO_4)_3 > Urea > CaCl_2 > Glucose So order of BP = Al_2(SO_4)_3 > Urea > CaCl_2 > Glucose So Answer will be I < II < III < IV
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