Q14 of 26 Page 1

A solution is prepared by dissolving 5 g of non-volatile solute in 95 g of water. It has a vapour pressure of 23.375 mm Hg at 25°C. Calculate the molar mass of the solute. (Vapour pressure of pure water at 25°C is 23.75 mm Hg)

Given, Mass of solute, w2 = 5g


Mass of solvent, w1 = 95g


Molar mass of solvent, M1 = 18 g/mol


Molar mass of solute, M2 = ?


Vapour pressure of pure water, P° = 23.75 mm Hg


Vapour pressure of solution, P = 23.375 mm Hg


We know, =


=


M2 =


= 60 g/mol


More from this chapter

All 26 →
12

Calculate E°cell for the following reaction at 25oC:

A + B2+(0.001 M) A2+(0.0001 M) + B


Given: Ecell = 2.6805, 1 F = 96500 C/mol


 13

Differentiate between the following:

(i) Solution and Colloid


(ii) Homogeneous catalysis and Heterogeneous catalysis


(iii) O/W emulsion and W/O emulsion


 15

(i) Name the method of refining to obtain low boiling metal like mercury.

(ii) What is the role of pine oil in froth floatation process?


(iii) Reduction of metal oxide to metal becomes easier if the metal obtained is in liquid state. Why?


 16

Examine the given defective crystal:


Answer the following questions:


(i) Is the above defect stoichiometric or non-stoichiometric?


(ii) Write the term used for this type of defect.


(iii) Why do silver halides show this type of defect?