1 g of water at `100^@C` is completely converted into steam at `100^@C`. 1 g of steam occupies a volume of 1650 cc . (Neglect the volume of 1 g of water at `100^@C`). At the pressure of `10^(5)N//m^(2)`, latent heat of steam is `540cals//g` (1 Calorie= 4.2 Joules).The increase in the internal energy in Joules is

Options

A. 2310
B. 2103
C. 1650
D. 2150

Answer

B

Explanation

`dQ = dU + dW`
`dU = dQ - dW` `[because 1 cal = 4.25 J]`
`dQ = ml`
`1 xx 540 xx 4.2 = 2268 J`
`dW = pdv`
`= 10^(5) xx 1650 xx (10^(-2)^(3)`
`[because " Volume of water is neglected"]`
` 165 J`
`therefore` `dU = 2268 - 165 = 2103 J`