Unit 4 Definitions

Question 0

Define ‘Bronsted-Lowry Acid’.

Answer 0

Proton donor.

Question 1

Define ‘order of reaction’.

Answer 1

Power of concentration term (in rate equation).

Question 2

Define ‘Bronsted-Lowry Base’.

Answer 2

Proton acceptor.

Question 3

Define ‘pH’.

Answer 3

pH = -log[H+]

Question 4

What is the ionic product of water?

Answer 4

Kw = [H+][OH-]

Question 5

Define ‘weak acid’.

Answer 5

Acid that slightly dissociates in aqueous solution.

Question 6

Define ‘weak base’.

Answer 6

A base that slightly dissociates in aqueous solution.

Question 7

Define ‘buffer’.

Answer 7

A solution which maintains pH despite the addition of acid or base.

Question 8

Define ‘chiral carbon’.

Answer 8

A carbon atom with four different groups attached.

Question 9

Define ‘enantiomer’.

Answer 9

Molecules with a chiral carbon atom that exist as two non-superimposable mirror images.

Question 10

Define ‘racemic mixture’.

Answer 10

A mixture containing an equal amount of each enantiomer.

Question 11

Define ‘nucleophile’.

Answer 11

Electron pair donor.

Question 12

Define ‘electrophile’.

Answer 12

Electron pair acceptor.

Question 13

Define ‘stereoisomer’.

Answer 13

A molecule with the same structural formula but with it’s atoms arranged differently in space.

Question 14

Define ‘retention time’.

Answer 14

The time taken for a particular substance to pass through a chromatography column.

Question 15

Define ‘enthalpy of formation’.

Answer 15

The enthalpy change when 1 mol of a compound is formed from its elements.

Question 16

Define ‘ionisation enthalpy’.

Answer 16

The minimum amount of energy required to remove one mole of electrons from one mile of atoms in the gaseous state.

Question 17

Define ‘enthalpy of atomisation’.

Answer 17

The enthalpy change for the formation of one mole of gaseous atoms from the element in its standard state under standard conditions.

Question 18

Define ‘bond association enthalpy’.

Answer 18

The enthalpy change to break the bond in 1 mol of gaseous molecules to form gaseous molecules.

Question 19

Define ‘electron affinity’.

Answer 19

Enthalpy change when one mole of gaseous atoms form one mole of gaseous negative ions.