Reacting mass calculations
The key to reacting mass calculations at A level is to have a foolproof method for setting them out so
Category: Calculations
Empirical vs. molecular formulae
Empirical formula: simplest ratio of the atoms of different elements in a compound Molecular formula: the actual number of each
Working with different units in chemistry
Factor Name Unit Common examples 106 mega M 103 kilo k kg 10-1 deci d dm 10-2 centi c cm
Atom economy
Atom economy or percentage atom economy is simply a measure of how ‘green’ a chemical process is – it essentially
Significant figures in chemistry
Rule 1: when adding or subtracting numbers, the answer should be quoted to the least number of decimal places in
Avogadro’s number and the mole
Often students arrive at A level knowing how to calculate the number of moles of a substance but with a