Geo-Scientist Prelims 2024 Chemistry Q58: Consider the following reactions :

Consider the following reactions :

1. H₂ (g) + ½O₂ (g) → H₂O (l); Δ_rH = −285·8 kJ mol⁻¹
2. ½N₂ (g) + O₂ (g) → NO₂ (g); Δ_rH = +33·2 kJ mol⁻¹

Which one of the following is correct with respect to the above reactions?

1. (a) Reaction 1 is endothermic and non-spontaneous at all temperatures
2. (b) Reaction 2 is exothermic and spontaneous at all temperatures
3. (c) Reaction 2 is endothermic and non-spontaneous at all temperatures
4. (d) Reaction 1 is exothermic and spontaneous at all temperatures