Stoichiometry

There is no stoichiometry without try: try out questions from the O Level Combined Chemistry papers

Be 100% sure about how to calculate percentage yield and percentage purity

It's big brain time, as you think backwards from the salt in question to infer the reagents and method

Fresh from the furnace of O Level

Learn stoichiometry and the mole concept by solving problems taken from O Level prelim papers. Answers and explanations are included.

Calculate how each element in a compound is pulling its weight, and use this to find the chemical formula empirically

Unit-less but meaningful: making sense of the mass of an atom with ratio

Sorry, we don't have 25% sugar here. How about 100 g/dm3 or 0.292 mol/dm3?

Look into the future and predict the amount of product formed, by identifying the mole ratio and limiting reactant

Gases of different masses taking up the same spaces

Learn how how to count, but in moles

Can you infer the formulae of ionic compounds, based on the charges of their constituent ions?