Stoichiometric Mixture
A mixture of reactants present in exactly the proportions required by the balanced equation, with no reactant in excess.
Formula / equation
n_A : n_B = a : b
Unit
mol
In depth
In a stoichiometric mixture every reactant is simultaneously limiting, so all are consumed together and the maximum possible conversion is achieved with no waste. Combustion at the stoichiometric air-to-fuel ratio releases the most heat per unit fuel and minimises unburnt emissions.
Examples in the real world
A 2:1 mole mixture of hydrogen and oxygen; the 14.7:1 mass ratio of air to petrol targeted by engine management systems.