5 x 1 hour lessons

This module builds a solid thermochemistry toolkit. You’ll define enthalpy changes, use standard-state conventions, and interpret reaction pathway diagrams. We’ll practise calorimetry (including q=mcΔT), use bond energy data, and then apply Hess’s Law to construct energy cycles and calculate enthalpy changes that can’t be measured directly.

By the end of this module you will be able to:

• distinguish exothermic and endothermic processes and the sign of ΔH

• draw and interpret reaction pathway diagrams (activation energy and ΔH)

• define and use standard conditions (298 K, 101 kPa shown by ⦵)

• define and use ΔHr, ΔHf, ΔHc, ΔHneut

• perform calorimetry calculations using q=mcΔT

• use bond energies (noting averages vs exact values) to estimate ΔHr

• apply Hess’s Law to construct simple energy cycles and calculate unknown enthalpy changes

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CIE Syllabus Points (9701):

• 5.1 Enthalpy change, ΔH

• 5.2 Hess’s Law