Answer
169.2 J
Step-by-step explanation
Given in the question,
mass of iron = 47g
specific heat capacity of iron = 0.450 (J/g 0C)
initial temperature = 12° C
final temperature = 20° C
The energy q needed to increase an object of mass m and specific heat capacity c by a temperature θ is given by:
q = mcΔt
q = 47(0.45)(20-12)
q = 169.2 J