Definitions Flashcards
Avagadro’s constant (L)
The number of atoms, molecules, ions or other chemical entities in one mole of a substance (6.02x10^23)
Molar concentration
Number of moles of a solute per litre of the solution - mol dm^3
Concentration
Amount per unit volume - usually mol dm^-3 or g dm^-3
Stoichiometry
The ratio in which reactants react and products are produced in whole numbers
Law of conservation of mass
States mass cannot be created or destroyed
Limiting reactants
Reacts that restrict the amount of product that a reaction can produce - usually (at least) one reactant will be in excess (too much) and another will be limiting
Empirical formula
Shows the simplest ratio of atoms of each element present in a compound
Molecular formula
Actual number of atoms of each element present in one molecule of a compound
Standard conditions
100kPa Pressure and 298k temperature (0° = 273k)
Titration
Technique used to find the concentration of an unknown solution by adding a known solution
End point of a titration
The point at which enough of the solution from the burette has been added to react completely with the unknown solution
Equivalence point of a titration
The point at which equal moles of acid and alkali are present
Titre
The amount of solution added to reach the endpoint
Acid
Substance which forms solutions with a pH of <7 and is a “proton donor” (provides H+ ions in solution in water)
Base
Substance which will act as a “proton acceptor” for an acid (accepts H+ ions)
