Calculations for AS and A level Chemistry
Being confident in tackling different types of mole calculation is the foundation upon which much of A level chemistry stands
From the blog
Understanding the relationship between the potential difference for an electrochemical cell and Gibbs energy
The spontaneity or feasibility of a reaction can be described by both a positive Ecell⦵ value or a negative value
The chemistry of corrosion
The rusting of iron can be summarised by the equation 4 Fe(s) + 3 O2(g) + H2O(l) ⇾ 2 Fe2O3•xH2O(s)
Predicting the feasibility of redox reactions using standard electrode potentials
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
Determining the potential difference of an electrochemical cell
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
What is an electrode potential?
If we place a strip of a metal such as zinc into a beaker containing zinc sulphate (the electrolyte) an
Using oxidation states to balance half equations
Often writing a half equation to show reduction or oxidation is straight forward – all we need to do is
Continue readingUsing oxidation states to balance half equations
Redox titration exam question practice
Redox titration questions are very popular on exam papers. They are usually set in an unfamiliar context and may require
Writing balanced redox equations using half equations
Given two half equations, we need to be able to write a fully balanced redox equation both under acidic and
Continue readingWriting balanced redox equations using half equations
Rules for assigning oxidation states
When the products of a reaction are molecular, or there are polyatomic ions such as SO42- involved, it is not
What is a redox reaction?
Reactions in which both oxidation and reduction occur are called redox reactions. The acronym OILRIG might be familiar, reminding us