How many kilojoules are needed to raise the temperature of 325 grams of water from 15.0 degrees c to 77.0 degrees c?

Given:

m = 325 g, the mass of water

ΔT = 77 - 15 = 62 °C, the change in temperature

Note that

c = 4.184 J / (g-°C), the specific heat of water.

Use the formula

Q = m*c*ΔT

where Q is the heat required for the change in temperature.

Q = (325 g) (4.184 J/g-°C) * (62 °C) = 8.43 x 10⁴ J

That is,

Q = 84.3 x 10³ J = 84.3 kJ

Answer: 84.3 kJ