inorganic definitions

Question 1

Relative isotopic mass

Answer 1

The mass of an atom relative to the mass of 1/12th of the mass of carbon-12.

Question 2

Relative atomic mass

Answer 2

The weighted mean mass of an atom relative to 1/12th of the mass of an atom of carbon-12.

Question 3

Bronsted-lowry acid

Answer 3

A species that is a proton, H+, donor.

Question 4

Bronsted-lowry base

Answer 4

A species that is a proton, H+, acceptor.

Question 5

Acid

Answer 5

A species that releases H+ ions in aqueous solution.

Question 6

Base

Answer 6

A compound that neutralises an acid to form a salt.

Question 7

Coordination number

Answer 7

The total number of coordinate bonds formed between a central metal ion and ligands.

Question 8

First electron affinity

Answer 8

The enthalpy change that takes place when one electron is added to each atom in one mole of gaseous atoms to form one mole of gaseous 1- ions.

Question 9

First ionisation energy

Answer 9

The energy required to remove one electron from each atom in one mole of gaseous atoms of an element to form one mole of gaseous 1+ ions.

Question 10

Ligand

Answer 10

A molecule or ion that can donate a pair of electrons to the transition metal ion.

Question 11

Ligand substitution

Answer 11

A reaction in which one or more ligands in a complex ion are replaced by different ligands.

Question 12

pi bond

Answer 12

A bond formed by the sideways overlap of 2 p orbitals, with the electron density above and below the plane of the bonded atoms.

Question 13

sigma bond

Answer 13

A bond formed by the sideways overlap of one orbital from each bonding atom, consisting of 2 electrons with the electron density centred around a line directly between the nuclei of the 2 atoms.

Question 14

Electronegativity

Answer 14

A measure of the attraction of a bonded atom for the pair of electrons in a covalent bond.

Question 15

Transition element

Answer 15

A d-block element which forms an ion with an incomplete d sub-shell.

Question 16

standard enthalpy change of atomisation

Answer 16

The enthalpy change that takes place when one mole of gaseous atoms forms from the elements in its standard state.

Question 17

standard enthalpy change of combustion

Answer 17

The enthalpy change that takes place when one mole of a substance reacts completely with oxygen under standard conditions, all reactants and products being in their standard states.

Question 18

standard enthalpy change of formation

Answer 18

The enthalpy change that takes place when one mole of a compound is formed from its constituent elements in their standard states under standard conditions.

Question 19

standard enthalpy change of hydration

Answer 19

The enthalpy change that takes place when one mole of isolated gaseous ions is dissolved in water forming one mole of aqueous ions under standard conditions.

Question 20

standard enthalpy change of neutralisation

Answer 20

The enthalpy change that accompanies the reaction of an acid by a base to form one mole of H2O(l) under standard conditions with all reactants and products in their standard states.

Question 21

standard enthalpy change of reaction

Answer 21

The enthalpy change that accompanies a reaction in molar quantities expressed in a chemical equation under standard conditions with all reactants and products being in their standard states.

Question 22

standard enthalpy change of solution

Answer 22

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