1 kg of water at 100 ° C is converted into steam at 100 ° C by boiling at atmospheric pressure. The volume of water changes from 1 . 00 × 10 - 3 m 3 as a liquid to 1 . 671 m 3 as steam. The change in internal energy of the system during the process will be (Given latent heat of vaporisation = 2257 kJ / kg , Atmospheric pressure = 1 × 10 5 Pa

Step-by-step solution

The work to be done in the process is given by d W = P d V = 1 × 10 5   Pa × ( 1 . 671 - 0 . 001 )   m 3 = 1 . 670 × 10 5   J The change in heat energy during the vaporisation process can be calculated as follows- Δ Q supplied  = 2257 × 1 × 10 3   J = 22 . 57 × 10 5   J Hence, the change in internal energy in the process is given by Δ U = Δ Q supplied - Δ W = ( 22 . 57 - 1 . 67 ) × 10 5   J = 20 . 9 × 10 5   J = 2090