(a) The temperature of 100 g of water is to be raised form `10^@C` to `40^@C` by adding steam at `100^@C` to it. Determine the mass of the steam required for this purpose.
(b) How much steam at `100^@C` will just melt 2700 g of ice at `-10^@C`?

Explanation

(a) If `m` is mass of steam.
`100xx1xx(40-10)=mxx540+mxx1xx(100-40)`
`3000=600M`
`m=5g`
(b) Let `m` is mass of steam,
`2700xx0.5[0(-10)]+2700xx80`
`=mxx540+mxx1xx(100-0)`
`2700xx85=640m`
`m=358.6g`