Ocr A2 Chemistry F325 Definitons

Front 1

Standard enthalpy change of solution

Back 1

The enthalpy change when one mole of a compound is completely dissolved in water under standard conditions

Front 2

Standard enthalpy of hydration

Back 2

The enthalpy change when one mole of gaseous ions is dissolved in water forming one mole of aqueous ions under standard conditions

Front 3

Standard enthalpy change of formation

Back 3

The enthalpy change when one mole of a compound is formed from its consitituent elements under standard conditions

Front 4

Lattice Enthalpy

Back 4

The enthalpy change when one mole of an ionic compound is formed from its gaseous ions under standard conditions.

Front 5

Enthalpy change of atomisation

Back 5

The enthalpy change when one mole of gaseous atoms forms from the element in its standard state.

Front 6

First electron affinity

Back 6

The enthalpy change when each gaseous atom in one mole of gaseous atoms gains an electron to form one mole of gaseous 1- ions

Front 7

First Ionisation energy

Back 7

The enthalpy change when each gaseous atom in one mole of gaseous atoms loses an electron to form one mole of gaseous 1+ ions

Front 8

Standard electrode potential

Back 8

The EMF of a half cell compared with a standard hydrogen half cell, measured at 298k, 1mol dm-3, 1 atm

Front 9

Transition element

Back 9

Is a d-block element that forms an ion with an incomplete d sub-shell

Front 10

Complex ion

Back 10

Is a transition metal ion bonded to one or more ligands by coordinate bonds

Front 11

Coordination Number

Back 11

is the total number of coordinate bonds formed between a central metal ion and its ligands

Front 12

Ligand

Back 12

is a molecule or ion that can donate a pair of electrons with the transition metal ion to form a coordinate bond

Front 13

Bidentate Ligand

Back 13

The ligand can donate two lone pairs of electrons to the central metal ion to form two coordinate bonds.

Front 14

Standard enthalpy of neutralisation

Back 14

is the enthalpy change that accompanies the neutralisation of an aqueous acid by and aqueous base to form one mole of H2O, under standard conditions

Front 15

Bronsted-lowry acid

Back 15

Proton donator

Front 16

Buffer Solution

Back 16

Is a mixture that minimises PH changes on addition of small amounts of acid or base