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
Interpreting the mass spectrum of an organic molecule
Mass spectrometry is a really powerful tool for helping us to piece together the structure of an organic molecule. Ionisation
Continue readingInterpreting the mass spectrum of an organic molecule
How to calculate the relative abundance of an isotope
We can calculate the percentage abundances for each of the isotopes in an element if we know the mass number
Continue readingHow to calculate the relative abundance of an isotope
How to calculate the relative atomic mass of an element from a mass spectrum
We know that relative atomic mass (Ar) is the average of (% abundance of an isotope x isotopic mass) for
Continue readingHow to calculate the relative atomic mass of an element from a mass spectrum
Time of flight mass spectrometer
A mass spectrometer is able to very accurately determine the relative atomic mass of an element, by measuring the mass
Using the Nernst equation to calculate the electrode potential of a half cell
The standard electrode potential for a half cell means exactly that – everything happening under standard conditions (298K, 100 kPa,
Continue readingUsing the Nernst equation to calculate the electrode potential of a half cell
Electrolysis of solutions
Electrolysis uses electricity (energy) to drive a non-spontaneous reaction which is useful for recharging batteries, splitting water to make hydrogen
The chemistry of fuel cells
Fuel cells commonly use the reaction between hydrogen and oxygen to produce a voltage, with water being the only waste
The chemistry of batteries
Modern storage cells (batteries) can be divided into the non-rechargeable kind (primary cells) and the rechargeable kind (secondary cells). Primary
Using the relationship between potential difference and Gibbs energy to calculate a value for the equilibrium constant, K
Ecell⦵ (the maximum potential difference between two half cells) is measured when the reactants are under standard conditions (1.00 mol
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