Definitions

Question 1

Intermediates?

Answer 1

Substances not shown in the overall equation as they are created and used up.

Question 2

Lattice enthalpy?

Answer 2

The formation of 1 mole of ionic lattice from gaseous ions.

Question 3

Enthalpy of solution?

Answer 3

When 1 mole of a solute is completely dissolved in water.

Question 4

Enthalpy of hydration?

Answer 4

1 mole of aqueous ions are formed from their gaseous ions.

Question 5

Entropy?

Answer 5

A measure of the dispersal of energy in a system or the degree of disorder.

Question 6

Standard entropy?

Answer 6

Entropy of 1 mole of a substance under standard conditions.

Question 7

Transition element?

Answer 7

D-block element that has at least one stable ion with an incomplete d subshell.

Question 8

D-block element?

Answer 8

Element where the highest energy electron is in the d subshell.

Question 9

Complex ion?

Answer 9

A central transition metal ion bonded to one or more ligands by coordinate bonds.

Question 10

Ligand?

Answer 10

An ion or molecule with a lone pair of electrons that can be donated to a transition metal to form a coordinate bond.

Question 11

Coordinate number?

Answer 11

The total number of coordinate bonds between a central metal ion and its ligand.

Question 12

Monodentate ligand?

Answer 12

A ligand that donates one pair off electrons to the central metal ion.

Question 13

Bidentate ligand?

Answer 13

One that donates two pair of electrons to the central transition metal ion forming two coordinate bonds.

Question 14

Stereoisomerism?

Answer 14

Same molecular and structural formula, but different arrangement of atoms in space.

Question 15

Optical isomerism?

Answer 15

Non-superimposable mirror images.

Question 16

Cis platin?

Answer 16

Anti cancer drug which binds to DNA in cancer cells ad prevents cell division.

Question 17

Acids?

Answer 17

Proton donor.

Question 18

Base?

Answer 18

Proton acceptors.

Question 19

Buffer?

Answer 19

A solution that minimises pH changes on addition of small amounts of acid or base.

Question 20

Oxidising agent?

Answer 20

Causes something to be oxidised but is in itself reduced.

Question 21

Reducing agent?

Answer 21

Causes something to be reduced, but is in itself oxidised.

Question 22

Standard electrode potential of a half cell?

Answer 22

The emf of a half cell compared with a standard hydrogen half cell measured at 298K, 1 atm and solution concentration 1 moldm-3.

Question 23

Fuel cell?

Answer 23

Uses the energy from the reaction of a fuel (H2 or hydrogen rich fuels such as methanol) with an oxidant (O2) to create a voltage.