One mole of an ideal gas is heated at constant pressure from `0^(@)C` to `100^(@)C`
(A) Calculate work done. (B) If the gas were expanded isothermally and reversibly at `0^(@)C` from 1 atm to some other pressure `P_(1)`, water must be the final pressure if the maximum work is equal to the work involned in (a)?

Answer

molar internal energy change =37.5 kj/mol, molar enthaply of vaporization =40.6kj/mol

Explanation

Solution (a) work involed in heating of gas
`W_(a) = - p.Delta V = - P (V_(2) - V_(1)) - 198.7`
`= -2.303 xx1xx9.87xx 273 log_(10). (1)/(P_(1)) :. P_(1) = 0.694 atm`