Question

Temperature of 100g of water is to be raised from 24°C to 90°C by adding steam to it. Mass of the steam required for this purpose is

Answer 1

Let m be the mass of steam required.
By principle of calorimetry
100×1×(90−24)=m540+m×1(100−90)
i.e.,550m=100×66⇒m=12g