Question

Classifies the given equations as endothermic and exothermic reactions. i) CH4 +2O2 → CO2 + 2H2 O ΔH° = −890.4 kJ mol−1 ii) NH4 NO3 → NH4 + NO3 ΔH° = +25 kJ mol−1 iii) NaCl(s) → Na+ (g) + Cl– (g) ΔH° = +788 kJ mol−1 iv) HCl(aq) + NaOH(aq) → NaCl (aq) + H2 O(l) ΔH° = −57.32 KJ mol−1​

Answer 1

Answer:

(i) , (iv) are exothermic reaction.

(ii), (iii) are endothermic reaction.

Explanation:

For a exothermic reaction (∆H = negative)

For a endothermic reaction (∆H = positive)