Definitions

Question 1

First Ionisation Energy

Answer 1

The energy required to convert one mole of gaseous atoms into gaseous ions with a a single positive charge

Question 2

Second/Third Ionisation Energy

Answer 2

The energy required to convert one mole of gaseous ions with a single/double positive charge into gaseous ions with a double/triple positive charge

Question 3

Standard Conditions

Answer 3

25°C(298K) and 1 atmosphere(100kPa)

Question 4

Enthalpy of Reaction

Answer 4

Enthalpy change when the number of moles of substances reacts, as written in the equation

Question 5

Standard enthalpy of combustion

Answer 5

The enthalpy change when one mole of a substance is completely burnt is oxygen under standard conditions

Question 6

Standard enthalpy of formation

Answer 6

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

Question 7

Standard enthalpy of neutralisation

Answer 7

The enthalpy change when one mole of water is produced in a neutralisation reaction under standard conditions

Question 8

Lattice enthalpy

Answer 8

The enthalpy change when one mole of an ionic compound is converted to gaseous ions.

Question 9

Enthalpy of atomisation

Answer 9

The enthalpy change when one mole of gaseous atoms is formed from the element in its atomic state

Question 10

First electron affinity

Answer 10

The enthalpy change when one mole of gaseous atoms is converted into gaseous ions with a single negative charge

Question 11

Enthalpy of solution

Answer 11

The enthalpy change when one mole of a solute dissolves in water

Question 12

Enthalpy of hydration

Answer 12

The enthalpy change when one mole of gaseous ions is converted to one mole of aqueous ions

Question 13

Conservation of energy

Answer 13

Energy cannot be created or destroyed but it can be changed from one form to another

Question 14

Hess’s Law

Answer 14

The enthalpy change for a reaction is independent of the route taken, provided the initial and final conditions are the same

Question 15

Average bond enthalpy

Answer 15

The energy required to break one mole of a given bond averaged over many compounds

Question 16

Bond enthalpy

Answer 16

The energy required to break one mole of a specific bond

Question 17

Reaction rate

Answer 17

The change of the concentration (amount) of a reactant or product with respect to time

Question 18

Order of reaction (with respect to a reactant)

Answer 18

The power to which the concentration of a reactant is raised in the rate equation

Question 19

Order of reaction (overall)

Answer 19

The sum of the powers to which the concentration terms are raised in the rate equation

Question 20

Rate constant

Answer 20

The proportionality constant which links the rate of the reaction to the concentrations in the rate equation

Question 21

Rate determining step

Answer 21

The slowest step in the mechanism

Question 22

Activation energy

Answer 22

The minimum amount of energy required for a reaction to occur

Question 23

Homogenous

Answer 23

A reaction in which all the reactants and products are in the same physical state

Question 24

Heterogenous

Answer 24

A reaction in which all the reactants and products are not in the same state

Question 25

Feasible/Spontaneously

Answer 25

A reaction for which free energy is less than 0 (/_\G<0)

Question 26

Entropy

Answer 26

A measure of disorder (randomness)

Question 27

Dynamic Equilibrium

Answer 27

Rate of forward reaction is equal to the rate of backward reaction and the amount of each reactant/product remains constant.

Question 28

Reversible

Answer 28

A reaction which goes in both the forward and backward directions.

Question 29

Equilibrium

Answer 29

A reversible reaction in which the amount of each reactant/product remains constant.

Question 30

Homogenous Equilibrium

Answer 30

A reaction in which all the reactants and products are in the same physical state.

Question 31

Heterogenous Equilibrium

Answer 31

A reaction in which the reactants and products are in a different physical state.

Question 32

Concentration.

Answer 32

Number of moles divided by volume.

Question 33

Bronsted

Answer 33

Proton donor

Question 34

Bronsted base

Answer 34

Proton acceptor

Question 35

Kw

Answer 35

kw= (H+)(OH-)

Question 36

Ka

Answer 36

Ka=[H+][A-]/[HA]

Question 37

pH

Answer 37

pH= -log10[H+]

Question 38

pKa

Answer 38

pKa= -log10Kw

Question 39

Buffer Solution

Answer 39

A solution which resists change in pH on addition of small amounts of acid or alkali

Question 40

Monobasic

Answer 40

Donates one proton per molecule

Question 41

Asymmetrical Centre

Answer 41

An atom which has four different atoms or groups attached

Question 42

Optical Isomers

Answer 42

Molecules which exist as non-superimposable mirror images

Question 43

Optically active

Answer 43

As sample which rotates the plane of plane polarised light

Question 44

Racemic Mixture

Answer 44

A 50:50 mixture of two optical isomers

Question 45

Monoester

Answer 45

An ester which contains only one ester group

Question 46

Transesterification

Answer 46

A reaction where the alkyl group of an ester is exchanged with the alkyl group of an alcohol

Question 47

Biodiesel

Answer 47

A fuel, similar to diesel, which is made from vegetable sources. E.g. from the reaction of rape seed oil with methanol