Which of the following reactions shows that the formation of CO₂ releases 393.5 kJ/mol?
a. C(s) + O₂(g) → CO₂(g) 393.5 kJ
b. C(s) + O₂(g) 393.5 kJ → CO₂(g)
c. C(s) + 2O(g) 393.5 kJ → CO₂(g)
d. C(s) + O(g) → CO₂(g) 393.5 kJ