Question

CHEM PLZ HELP, Which thermochemical equation represents the most exothermic reaction?

Question 7 options:

16CO2 + 18H2O → 2C8H18 +25O2 , ΔH = +5,471 kJ/mol


NH4Cl → NH4+ (aq) + Cl– (aq) , ΔH = +14.8 kJ/mol


C5H12 (g) + 8O2 (g) → 5CO2 (g) + 6H2O (l), ΔH = –3,536.1 kJ/mol

Answer 1

The answer is option 3, C5H12 + 8O2 → 5CO2 + 6H2O.

Step-by-step explanation:

In an exothermic reaction, the energy change(ΔH) will always be a negative value.

For endothermic reaction, the energy change's value is positive.

In the options above, option 1 and 2 are endothermic reaction.