- Exothermic- Describes a process which emits energy.
- Endothermic- Describes a process that absorbs energy.
- Standard State- The standard state gives the state (solid, liquid or gas) and colour of a substance at room temperature (298K) and at 1 atmosphere.
- Enthalpy change of combustion- The process when one mole of a compound is completely burnt in excess oxygen
- Enthalpy change of reaction- The energy change at constant pressure and a stated temperature for a process in which a specified amount of reactants are converted into products.
- Enthalpy change of formation- The process when one mole of a compound is formed from its elements in their standard states.
- Hessís Law- The enthalpy change of a reaction is the same, whether it occurs in one step or a series of steps, providing that the initial and final conditions are the same for each route.
- Entropy- The measure of how disordered a system is.
- Catalyst- A substance which changes the rate of a chemical reaction without undergoing any change itself.
Useful books for revision:
Revise AS Chemistry for Salters (Written by experienced examiners and teachers of Salter's chemistry)
Revise AS Chemistry for Salters (OCR) (Salters Advanced Chemistry)