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Browse all science resourcesUse hot and cold reactions to distinguish the system from its surroundings, explain energy conservation, and classify endothermic and exothermic changes.
Connect thermometer observations, energy-transfer directions and energy profiles. Students practise the sign of enthalpy change, enthalpic stability, graph interpretation and error correction.
Build Q = mcΔT from scaling arguments, interpret specific heat capacity and practise calorimetry calculations with consistent units. The lesson also introduces standard-state conventions and experimental assumptions.
Convert calorimetry measurements into molar enthalpy changes through neutralisation, dissolution and combustion examples. Students check solution or water mass, reacting moles, energy units and the physical meaning of the sign.
Evaluate why experimental enthalpy values differ from accepted data. Students analyse heat transfer, apparatus heating, incomplete combustion and evaporation, then use cooling-curve extrapolation and justify practical improvements.
