Answer:
Option D. 4.02 kJ
Explanation:
A simple calorimetry problem
Q = m . C . ΔT
ΔT = Final T° - Initial T°
C = Specific heat capacity
m = mass
Let's replace the data
Q = 125 g . 2.42 J/g∘C . (34.8°C -21.5 °C)
Q= 4023.25 J
We must convert the answer to kJ
4023.25 J . 1kJ /1000 =4.02kJ
The answer is 40 grams. If gold is 20 grams per mL and you have 2 mLs, you get 40 grams of gold. Just add 20 + 20 or multiply 2 x 20 to get 40.