finding the mole using the realative atomic mass:mole = mass used / relative atomic mass
finding the mole of a compund:mole = mass used / relative molecular mass
finding the mole in a solution:mole = volume (dm^3) * molarity
finding the mole of any gas:mole = volume (dm^3) / 24 dm^3
finding the percentage yield:% yield = (mass produced / theoretical yield) * 100
finding the percentage purity:% purity = (actual mass reacted / initial mass used) * 100
hope this helps