A potential-energy diagram shows the reactants of a chemical process at 120 kJ and…

CHEMISTRY · Single correct · A Level · Chemistry · Energetics · Energetics

Problem

A potential-energy diagram shows the reactants of a chemical process at 120 kJ and the products at 75 kJ, both relative to the same reference line. Which statement about the enthalpy change for the process is correct? (a) ΔH=+45 kJ, and the process is endothermic.\Delta H = +45\text{ kJ},\text{ and the process is endothermic.} (b) ΔH=+75 kJ, and the process is endothermic.\Delta H = +75\text{ kJ},\text{ and the process is endothermic.} (c) ΔH=−45 kJ, and the process is exothermic.\Delta H = -45\text{ kJ},\text{ and the process is exothermic.} (d) ΔH=+195 kJ, and the process is exothermic.\Delta H = +195\text{ kJ},\text{ and the process is exothermic.}

Related theory

Browse the problem library