- What are hypotonic and hypertonic solutions? 4% sucrose solution is isotonic with 3% solution of an unknown organic substance. Calculate the molecular mass of the unknown solute. 3
- Define vapour pressure. How much urea (molar mass 60 g/mol) should be dissolved in 50 g of water so that its vapour pressure at room temperature is reduced by 25%. 3
- With the help of a suitable diagram show that the lowering of V.P. of a solution containing non volatile solute causes a lowering of freezing point of the solvent. 2
- Differentiate between ideal and non ideal solutions taking suitable example. 2
- State Henry’s law. State its two applications. 2
- When is the value of Van’t Hoff factor greater than one and less than one? What is the Van’t Hoff factor for 0.1 M BaCl2 which is 90% dissociated? 2
- Give reasons: 2
(a) The relative lowering of vapour pressure of 0.1 M NaCl and 0.1 M urea solution at the same temperature is not found to be same.
(b) Aquatic life is more comfortable in winters than in summers.
- 2g of benzoic acid (C6H5COOH) dissolved in 25 g of benzene shows a depression in freezing point equals to 1.62 K. Molal depression constant for benzene is 4.9 K Kg/mol. What is the percentage association of acid if it forms dimer in solution? 3
- What is the effect of temperature on molarity and molality of a solution? 1