The initial temperature of the gold was 84 K.
Step 1. Calculate the temperature change.
The formula for the heat (q) absorbed is
q = mCΔT
We can solve this equation to get
ΔT = q/(mC)
q = 12 000 J; m = 800 g; C = 0.129 J·K⁻¹g⁻¹
∴ ΔT = 12 000 J/(800 g × 0.129 J·K⁻¹g⁻¹) = 116 K
Step 2. Calculate the initial temperature
ΔT = T_f – T_i = 200 K – T_i = 116 K
T_i = 200 K – 116 K = 84 K
