Q9 of 30 Page 1

18 g of glucose, C6H12O6 (Molar mass = 180 g mol-1) is dissolved in 1 kg of water in a sauce pan. At what temperature will this solution boil? (Kb for water =0.52 K kg mol-1, boiling point of pure water =373.15K)

Weight of solvent H2O (W1) = 1kg = 1000gm


Molar mass of solvent H2O = 18gm


Weight of solute (C6H12O6 ) (W2) = 18gm


Molar mass of solute (M2) = 180gm


∴ Moles of solute = = 0.1moles


Kb for water =0.52 K kg mol-1


Boiling point of pure water =373.15K


∴ Elevation in boiling point ΔTb =


=


=0.052K


∴ ΔTb = Tb – T°b [Tb = Boiling point of solution]


[T°b =Boiling point of pure water]


0.052 = Tb – 373.15


∴ Tb = 373.202K


Hence, boiling point of the solution is 373.202K


More from this chapter

All 30 →
7

Arrange the following in increasing order of their basic strength in aqueous solution:

CH3.NH2, (CH3)3N, (CH3)2NH


 8

What are three types of RNA molecules which perform different functions?

 10

The conductivity of 0.20 M solution of KCl at 298 K is 0.025 Scm-1. Calculate its molar conductivity.

 11

Write the dispersed phase and dispersion medium of the following colloidal systems:

(i) Smoke


(ii) Milk


OR


What are lyophilic and lyophobic colloids? Which of these sols can be easily coagulated on the addition of small amounts of electrolytes?