A sample of iron absorbs 825 J of heat upon which the temper

A sample of iron absorbs 82.5 J of heat, upon which the temperature of the sample increases from 21.5°C to 27.5°C. If the specific heat of iron is 0.450 J/g-K, what is the mass (in grams) of the sample?

Solution

by definition

heat = mass x specific heat x temp change

q = m x Cs x dT

82.5 J = m x 0.45 (J/gC) x (27.5 - 21.5 ) C

m =( 82.5 / (0.45) (6) ) g

m = 30.55 g

so

the mass of the sample is 30.6 g