Studied by 2 people
RELATIVE ATOMIC MASS
the weighted mean mass of an element compared with 1/12th of a carbon 12 atom
relative isotopic mass
the mass of an atom of an isotope compared with 1/12th of a carbon 12 atom
homologous series
a group of organic compounds with the same functional group and similar chemical properties, differing by a constant unit, typically a -CH2- group.
covalent bond
the strong electrostatic attraction between the the shared electrons in the covalent bond and the nuclei of the bonded atoms
metallic bond
the strong electrostatic attraction between the positive metal ions and the delocalised electrons
ionic bond
electrostatic attractions between the positive and negative ions in all directions in a giant ionic lattice
electrophile
a species that accepts a pair of electrons to form a covalent bond
nucleophile
donates a pair of electrons to form a covalent bond
Le Chatalier’s principle
when a system in dynamic equilibrium is subjected to a change from the external environment, it will shift the equilibrium to counteract the change
1st electron affinity
the enthalpy change when 1 electron is added to each atom in a mole of gaseous atoms to form -1 gaseous ions (exothermic), the 2nd EA is endothermic
1st ionisation energy
the enthalpy change when 1 mole of electrons are removed from 1 mole of gaseous atoms to from +1 gaseous ions (electron from the outershell)
lattice enthalpy
the enthalpy change when 1 mole of an ionic compound is formed from its gaseous ions under standard contitions
enthalpy change of atomisation
when 1 mole of gaseous atoms is formed from an element in its standard state
enthalpy change of hydration
enthalpy change when gaseous ions are dissolved in water to form 1 mole of aqueous ions (exothermic)
enthalpy change of solution
1 mole of solute dissolved in a solvent, can be exothermic or endothermic
entropy
the measure of dispersal of energy in a system
standard entropy
entropy of 1 mole of a substance under standard conditions
free energy change
Gibbs’ equation: delta G = delta H - TdeltaS
standard conditions
298K, 1 atm(100/101kPa) and 1moldm^-3
homolytic fission
the breaking of a covalent bond wherein one of the shared electrons going to each atom, forming two radicals
hetereolytic
the breaking of a covalent bond when both of the shared electrons go to one of the atoms, forming a positive and negative ion
electronegativity
a measure of attraction of a bonded atom for the pair of electrons in a covalent bond
equivalence point
a point in the titration when the volume of first solution has reacted exactly with the volume of second solutions
activation energy
the minimum amount of energy required for a reaction to take place
aromatic
contains one or more benzene rings
alicyclic
containing carbon atoms joined together in a ring but the ring isn’t aromatic
aliphatic
carbon atoms joined together in a straight chain/branched chain
