Statement I: The magnitude of enthalpy of combustion of diamond is greater than that of graphite.<br — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

Graphite is the thermodynamically most stable allotrope of carbon, meaning diamond is at a higher energy state (ΔfH° = +1.9 kJ/mol). Therefore, when diamond is burned completely to $CO_2$, it releases slightly more heat than graphite. Thus, Statement I is correct, and Statement II is correct and is the proper explanation.