Definitions

Question 1

Molecular formula

Answer 1

A formula which shows the actual number of atoms of each element in a molecule

Question 2

Molar gas volume

Answer 2

The volume of one mole of gas under specified conditions of temperature and pressure e.g 24dm3 at 20C and one atmosphere pressure

Question 3

Homologous series

Answer 3

Compounds which have the same general formula, similar chemical properties and successive members differ by CH2

Question 4

Functional group

Answer 4

The part of a structure which determines the characteristic reactions of the compound

Question 5

Structural isomers

Answer 5

Molecules which have the same molecular formula but different structural formula

Question 6

Stereoisomers (geometric)

Answer 6

Have the same structural formula but different 3D spatial arrangements (are non-superimposable)

Question 7

Empirical Formula

Answer 7

A formula which shows the simplest number ratio of atoms of each element compound

Question 8

Saturated hydrocarbon

Answer 8

Contains no c=c or ctriplec bond

Question 9

Hydrocarbon

Answer 9

Contains hydrogen and carbon only

Question 10

Thermal cracking

Answer 10

Breaking down large molecules into smaller molecules using heat

Question 11

Subsitution

Answer 11

Replacing one atom or group with a different atom or group

Question 12

Homolytic fission

Answer 12

Bond breaking in with one of the shared electrons goes to each atom

Question 13

Free radical

Answer 13

A particle with an unpaired electron

Question 14

Catalyst

Answer 14

A substance which alters the speed of a chemical reaction but does not get used up

Question 15

Unsaturated hydrocarbon

Answer 15

Contains at least one c=c or ctriplec bond

Question 16

Sigma bond

Answer 16

A covalent bond formed by the linear overlap of atomic orbitals resulting in free rotation along bond axis

Question 17

Pi bond

Answer 17

A covalent bond formed by the sideways overlap of p orbitals resulting in it being restricted along the bond axis

Question 18

Bond length

Answer 18

The distance between the nuclei of two covalently bonded atoms

Question 19

Hydrogenation

Answer 19

Addition of hydrogen across a c=c

Question 20

Electrophile

Answer 20

An ion or molecule that attacks regions of high electron density

Question 21

Heterolytic fission

Answer 21

Bond breaking in which the shared electrons go to one atom

Question 22

Polymerisation

Answer 22

Joining together of small molecules to form a large molecule

Question 23

Primary alcohol

Answer 23

An alcohol which has only one carbon directly attached to the same carbon as the OH group (except methanol)

Question 24

Secondary alcohol

Answer 24

An alcohol which has 2 carbons directly attached to the same carbon as the OH group

Question 25

Tertiary Alcohol

Answer 25

An alcohol which has 3 carbons directly attached to the same carbon as the OH group

Question 26

Nucleophile

Answer 26

An ion or molecule with a lone pair of electrons that attacks regions of low electron density

Question 27

Hydrolysis

Answer 27

Breaking up of molecules by reaction with water

Question 28

Elimination

Answer 28

A reaction in which a small molecule is removed from a larger molecule

Question 29

Miscibility

Answer 29

Liquids which mix in all proportions ie form a single layer

Question 30

Esterification

Answer 30

A reaction between an alcohol and a carboxylic acid or acyl chloride to produce an ester