This can be done in the following way; 1 determining the heat required to convert 0° C ice to 0°C water Heat of fusion of water = 334 J/g Therefore; Heat = 50 g × 334 J/g = 16700 J 2. Determining the heat required to raise the temperature of water from 0° C to 100°C. Specific heat of water is 4.18 J/g°C Change in temperature is 100°C Therefore; Heat = 50 g × 4.18 J/g°C × 100 = 20900 J 3. Determining the heat required to convert 100 ° C water to 100°C vapor Heat of vaporization of water = 2257 J/g Heat = Mass of water × heat of vaporization Heat = 50 g × 2257 = 112850 J 4. Determining the heat required to go from 100° C to 120° vapor specific heat of vapor = 2.09 J/g°C Heat = mass × Specific heat of vapor × change in temperature = 50 g × 2.09 ×(120-100) = 2090 J
Therefore the total heat required is = 16700 J + 20900 J + 112850 J + 2090 J = 152540 J or 152.54 kJ