definitions Flashcards
atomisation
1 mole of gaseous atoms formed
combustion
1 mole of substance burned with excess oxygen
hydration
1 mole of gaseous ions dissolved sufficient water to form a very dilute solution
neutralisation
1 mole of water formed from alkali and acid
solution
1 mole of ionic solid dissolved sufficient water to form a very dilute solution
lattice energy
energy change of 1 mole of an ionic compound formed from its gaseous ions
SEP
voltage produced when a standard half-cell (1.00 moldm-3 298K) is connected to standard hydrogen electrode
under sc
SCP
diff between the 2 sep between two specified half cells
kw
equ constant of ionisation of water
ka
the equilibrium constant for the dissociation of a weak acid
adsorption
1st stage in heterogenous catalysis, when reactant molecules make bonds with atoms on the catalyst surface
bidentate ligand
a ligand that forms two coordinate bonds to the central transition metal ion in a complex
bond energy
the energy required to break one mole of a particular covalent bond in the gaseous state
units : kJmol-1
buffer solution
a solution that minimises significant changes in the pH when small amounts of acids and alkalis are added
carbocation
an alkyl group with a single positive charge on one of its carbon atoms, CH3+
catalysis
the increase in rate of a chemical reaction brought about by the addition of particular substance which is not used up by the reaction
desorption
last stage in heterogeneous catalysis
bonds holding the molecular of product to the surface of the catalyst are broken, and the product molecules diffuse away from the surface of the catalyst
diazotisation
the reaction between phenylamine and nitrous acid(HNO2) to give a diazonium salt in the first step in preparing azo dye