Question

What is the heat required in kilocalories to convert 2 kg of ice at 0°C completely into steam at 100°C?

Answer 1

The total amount of heat is the sum of the heat required to convert the ice to water, raise the temperature of water from 0 to 100°, and convert the heated water to steam. The heats are the product of the mass and the specific heats.
  ice to water:   (2000 g) x 0.50 cal/g = 1000 cal
  raising of temp:  (2000 g) x 1 cal/g°C = 2000 cal
  water to steam:  (2000 g) x 0.48 cal/g = 960 cal
The total amount of heat is equal to 3960 calories or 3.96 kcal.