According to Table I, which equation represents a change resulting in the greatest quantity of energy released? 2C(s) + 3H2(g) → C2H6(g) 2C(s) + 2H2(g) → C2H4(g) N2(g) + 3H2(g) → 2NH4(g) N2(g) + O2(g) → 2NO(g)
The answer is N2+3H2->2NH4. You can get the heat change on Table I. After checking the table I, you can get the ΔH for every reaction. The positive sign means absorbing energy and negative sign means releasing energy.