Topic 6: Definitions

Question 1

Define a hydrocarbon

Answer 1

A compound that only contains carbon and hydrogen atoms

Question 2

Define Saturated

Answer 2

a compound only containing single bonds

Question 3

Define Unsaturated

Answer 3

A compound containing one or more multiple bonds (double triple)

Question 4

Displayed formula

Answer 4

Shows:

-Every atom and every bond

Question 5

Skeletal formula

Answer 5

shows the bonds between carbon atoms

Question 6

molecular formula

Answer 6

shows the actual numbers of each atom in the molecule

Question 7

Empirical formula

Answer 7

the simplest whole-number ratio of the formula

Question 8

Structural isomers

Answer 8

Compounds with the same molecular formula but with different structural formulae

Question 9

Stereoisomers

Answer 9

Compounds with the same structural formula but different atoms or groups arranged differently in 3D

Question 10

Geometric isomers

Answer 10

Compounds containing a C=C bond with atoms or groups attached at different positions (E, Z)

Question 11

Restricted rotation

Answer 11

C=C is fixed so there can be no rotations

Question 12

Fractional distillation

Answer 12

The process used to separate a liquid mixture into fractions by boiling and condensing

Question 13

Cracking

Answer 13

Breakdown of molecules into shorter ones by heating them with a catalyst (Zeolite)

Question 14

Reforming

Answer 14

Conversion of straight-chain hydrocarbons into branched-chain and cyclic hydrocarbons

Question 15

Complete Combustion

Answer 15

This means all the atoms in the fuel are fully oxidised

Question 16

Incomplete combustion

Answer 16

Some of the atoms in the fuel are not fully oxidised

Question 17

Biofuels

Answer 17

Fuels obtained from living matter that has died recently

Question 18

Renewable

Answer 18

Energy sources that can be continuously replaced

• Bio diesel
• Bio alcohols

Question 19

Non-Renewable

Answer 19

Energy sources are not being replenished, except over geological timescales

Question 20

Radical

Answer 20

A species that contains an unpaired electron

Question 21

Homolytic Fission

Answer 21

Breaking of a covalent bond where each of the bonding pair of electrons leaves with one species forming a radical

Question 22

Initiation

Answer 22

Formation of radicals, usually as a result of bond breaking caused by ultraviolet radiation

Question 23

Propagation

Answer 23

Two steps that when repeated many times convert the starting materials into products

Question 24

Termination

Answer 24

Formation of a molecule from two radicals

Question 25

Substitution reaction

Answer 25

An atom or group is replaced with another atom or group

Question 26

Sigma Bonds

Answer 26

Covalent bonds formed when electron orbitals overlap end on

Question 27

Pi bonds

Answer 27

Covalent bonds formed when electron orbitals overlap sideways

Question 28

Steps for FRS (free radical substitution)

Answer 28

• Initiation
• Propagation
• Termination

Question 29

What is meant by the term functional group?

Answer 29

An atom or group of atoms in a molecule that is responsible for its CHEMICAL reactions

Question 30

What is meant by the term homologous series?

Answer 30

Family of compounds with the SAME FUNCTIONAL group but different molecular formula (differ from next member by CH2)