Critical phenomenon, calculation and determination of

Problem 10 What do you understand by critical temperature and critical pressure in relation to vander Waals equation and critical phenomenon. Calculate the values of critical constants in terms of vander Waals constants. How are the values of critical constants determined experimentally  

Starting from vander Waals equation find the values of critical constants. 

Write a short note on continuity of stale. (Meerut 2002,2000) 

The curves which are obtained by plotting pressure against volume at various constant temperatures are known as isotherms (isos = equal therm = heat). Andrews obtained isotherms of carbon dioxide at different temperatures which are shown in figure (7). 

Andrews observed that if the temperature of C02 was above 31.1°C it cannot be liquefied, whatever the pressure may be. Other gases also behave similarly. So, for every gas there is a limit of temperature beyond which it cannot be liquefied, whatever high pressure may be. This limit of temperature is known as critical temperature (Tc) of the gas. The pressure required to 

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