Edexcel IAL Chemistry AS 6.6 Hess's Law and enthalpy cycles
Edexcel IAL Chemistry AS 6.6 Hess's Law and enthalpy cycles
Balance the target equation, place common cycle species correctly, multiply enthalpies by coefficients and reverse signs whenever an arrow or reaction is reversed.
How this is tested
- Complete Hess cycles with correct species, state symbols, arrows and coefficients.
- Calculate reaction enthalpy from formation, combustion or experimental values.
- Reverse signs and apply stoichiometric multiples when combining cycle routes.