To calculate the amount of energy required to increase the temperature of a substance, we can use the formula:
q = m * C * ΔT
where:
q is the heat energy (in joules),
m is the mass of the substance (in grams),
C is the specific heat capacity of the substance (in J/g°C), and
ΔT is the change in temperature (in °C).
Given:
m = 245 g (mass of water)
C = 4.184 J/g°C (specific heat capacity of water)
ΔT = 81.6°C - 28.4°C = 53.2°C (change in temperature)
Plugging in the values into the formula:
q = 245 g * 4.184 J/g°C * 53.2°C
Calculating the value:
q ≈ 55480.392 J
Since the question asks for the energy in kilojoules (kJ), we can convert the result:
q ≈ 55.480392 kJ
Therefore, approximately 55.480392 kJ of energy is required to increase the temperature of 245 g of water from 28.4°C to 81.6°C.