The ultimate A level chemistry resource
A redox reaction consists of two half reactions – an oxidation and a reduction reaction. If we take a pair
Continue readingPredicting the feasibility of redox reactions using standard electrode potentials
We can link any two half cells together to form an electrochemical cell. A high resistance voltmeter prevents current (electrons)
Continue readingDetermining the potential difference of an electrochemical cell
If we place a strip of a metal such as zinc into a beaker containing zinc sulphate (the electrolyte) an
Reactions are either endothermic or exothermic – the heat transferred during a chemical reaction is either moving from the system
Continue readingUsing bond enthalpies to calculate an enthalpy change of reaction
What is enthalpy exactly? An enthalpy change is the heat transferred at constant pressure by a chemical reaction Heat changes
Continue readingEnthalpy cycles, Hess cycles, thermochemical cycles
Determining either the enthalpy change of neutralisation, or the enthalpy change for a classic displacement reaction (they are pretty much
You can calculate an experimental value for the enthalpy change of combustion for a fuel very simply – this is
Continue readingHow to calculate enthalpy of combustion of a fuel
Thermochemistry is all about the energy changes that happen alongside chemical reactions. Chemical reactions either release heat (exothermic) or
An indicator is used to follow the progress of an acid-base titration and the end point of the reaction is
Continue readingHow to choose an indicator for an acid-base titration
1. Strong acid – strong base titrations Imagine we are titrating a strong acid such as hydrochloric acid against a
Continue readingHow to explain the shape of a titration curve