WAEC - Chemistry (2017 - No. 26)
When Magnesium reacts with oxygen, heat is
absorbed and the reaction is endothermic
evolved and the reaction is endothermic
evolved and the reaction is exothermic
absorbed and the reaction is exothermic
Explication
The Magnesium actually reacts with oxygen in the air, is burnt and produces a bright light. The bright light emits a lot of heat so the reaction is exothermic.