Quantitative Chemistry – Definitions
Actual yield: The amount of product actually produced by a reaction.
*Atom economy: The measure of the amount of starting materials that end up
as useful products.
Avogadro constant: The number of atoms, molecules or ions in a mole of a
given substance.
*Avogadro’s law: Equal amounts in moles of gases occupy the same volume
under the same conditions of temperature and pressure.
Concentration: The amount of substance (e.g. the mass) in a certain volume of
a solution.
Conservation of mass: The law of conservation of mass states that no atoms
are lost or made during a chemical reaction so the mass of the products equals
the mass of the reactants.
Limiting reactant: The reactant that is completely used up since it limits the
amount of products formed.
*Mole: Chemical amounts are measured in moles. The mole is the unit for
amount of substance. The symbol for the unit mole is mol.
*Percentage by mass: A value representing the concentration of an element in
a compound
or a component in a mixture. It is calculated by the mass of a component
divided by the total mass of the mixture, multiplied by 100.
*Percentage yield: The percentage ratio of the actual yield of product from a
reaction compared with the theoretical yield.