Answer:
3065.63 J = 3.066 kJ.
Explanation:
Q = m.c.ΔT,
where, Q is the amount of heat needed to warm Fe (Q = ??? J).
m is the mass of Fe (m = 125.0 g).
c is the specific heat capacity of Fe (c = 0.45 J/g.°C).
ΔT is the difference in T (ΔT = final temperature - initial temperature = 78.0°C - 23.5°C = 54.5°C).
∴ Q = m.c.ΔT = (125.0 g)(0.45 J/g.°C)(54.5°C) = 3065.63 J = 3.066 kJ.