Question

What is the mass of a sample of iron if that sample lost 2300J of heat energy when it cooled from 80 oC to 30°C? The specific heat of iron is 0.449 J /g °C.

Answer 1

102 grams.
Equation:
Quantify of heat = mass x specific heat x difference in temperature
We have: quantity of heat : 2300J
specific heat: .449 J/g
difference in t: 80 - 30 = 50
Solve for mass: 2300 = mass x 0.449 x 50
mass = 102.449
2 sig-figs --> 102 grams