Explain the following:
(i) Drops of liquid assume a spherical shape.
(ii) The level of mercury in a capillary tube is lower than the level outside when a capillary tube is inserted in mercury.

Liquid that wets glass rises in a capillary tube or oil rises in the wick of an oil Jamp. Explain.

Explain the following:
(i) The boiling point of water (373 K) is abnormally high when compared to that of H₂S (211·2K).
(ii) Liquids like ether and acetone are kept in cool places. 
(iii) Tea or coffee is sipped from a saucer when it is quite hot.
     

Explain briefly the term viscosity. Define coefficient of viscosity. What are its units?

Which one in each of the following pairs is more viscous?
(i) Coconut oil,  castor oil
(ii) glyercine,  kerosene
(iii) soft drink, aerated water (soda water)? 

What is the effect of temperature on:
(i) density            
(ii) surface tension
(iii) viscosity            
(iv) the vapour pressure of a liquid?

What is the effect of pressure on:
(i) volume
(ii) boiling point
(iii) viscosity of a liquid?

Explain briefly:
(i) Dispersion or London forces
(ii) Dipole-dipole forces.

169.

Describe briefly dipole-induced dipole forces.