1. Which of the following equations represents standard heat of formation of C₂H₄?AC(graphite) + H2(g) → half C2H4(g)B2C(diamond) + 2H2(g) → C2H4(g)C2C(graphite) + 2H2(g) → C2H4(g)D2C(diamond) + 4H(g) → C2H4(g)