Calculate the increase in internal energy of 1 kg of water at `100^(@)C` when it is converted into steam at the same temperature and at 1 atm (100 kPa). The density of water and steam are `1000 kg m^(-3) and 0.6 kg m^(-3)` respectively. The latent heat of vapourisation of water `2.25 xx 10 ^(6)J kg ^(-1)`

Options

A. `2. 99 xx 10 ^(6) J`
B. `3.25 xx 10 ^(6) J`
C. `3.02 x 10 ^(6) J`
D. `2.08 xx 10 ^(6) J`

Explanation

`W =- P Delta V = Delta n RT = 55.56 xx 8.314 xx 373 =- 0. 172 xx 10 ^(6)`
Heat given, ` q =2.25 xxx 10 ^(6) J , Delta U = 2. 25 xx 10 ^(6) - 0. 172 xx 10 ^(6) = 2. 078 xx 10 ^(6) J`