unified atomic mass unit
1/12 the mass of a carbon-12 atom
relative atomic mass
the weighted average of the masses of the molecules relative to 1/12 of the mass of a carbon-12 atom
relative isotopic mass
the mass of the isotope relative to 1/12 of the mass of a carbon-12 atom
relative molecular mass
weighted average of the masses of the molecules relative to 1/12 of the mass of a carbon-12 atom
relative formula mass
weighted average of the masses of the formula unit relative to 1/12 of the mass of a carbon-12 atom
mole
the amount of substance which contains the same number of particles as there are atoms in exactly 12g of carbon-12
Avogadro’s constant
the number of atoms in one mole of c12 which is 6.022×10²3
limiting reagent
the reactant that governs the maximum amount of product that can be formed (the smallest number of moles on the reagent side, using the mole ratio)
percentage yield
percentage of the theoretical yield achieved in practice ( this is how much product is made in an incomplete reaction, compared to how much could be made if the reaction was 100% complete )
percentage purity
the actual mass reacted/the initial mass used expressed as a percentage ( this is how pure as a percentage )
empirical formula
the simplest whole number ratio of atoms present in a substance
molecular formula
the actual number of atoms of each element presents in a substance.