How many kJ of heat are needed to raise the temperature of 467 g of water from 21°C to 100°C in preparing a cup of coffee? Round your answer to the nearest integer. ?kJ

Answer 1

This is an application of the heat formula Q = m c ΔT, where c in this case is the specific heat capacity of water 4186 J/kg Cº. Note these units: the mass must be in kg, and the answer will be in J, not kJ. So the Joules of heat are (0.467 kg) (4186) (100 - 21) = 154,000 J which yields 154 kJ.