Basic Concepts and Hydrocarbons

Question 1

What is nomenclature?

Answer 1

The naming system for compounds.

Question 2

What is a homologous series?

Answer 2

A series of organic compounds that have the same functional group with successive members differing by CH2.

Question 3

What is an aliphatic hydrocarbon?

Answer 3

A hydrocarbon with carbon atoms joined together in straight or branched chains.

Question 4

What is an alicyclic hydrocarbon?

Answer 4

A hydrocarbon with carbon atoms joined together in a ring structure but it is not aromatic.

Question 5

What is an aromatic hydrocarbon?

Answer 5

A hydrocarbon that contains at least one benzene ring.

Question 6

What is a general formula?

Answer 6

The simplest algebraic formula for a homologous series.

Question 7

What is a displayed formula?

Answer 7

A formula that shows the relative positions of atoms and the bonds between them.

Question 8

What is a structural formula?

Answer 8

A formula that shows the minimum detail for the arrangement of atoms in a molecule.

Question 9

What is a skeletal formula?

Answer 9

A simplified structural formula drawn by removing hydrogen atoms from alkyl chains.

Question 10

What are unsaturated organic chemicals?

Answer 10

Organic chemicals that contain at least one carbon-carbon double bond.

Question 11

What are saturated organic compounds?

Answer 11

Organic compounds that contain only single covalent bonds.

Question 12

What is a molecular formula?

Answer 12

A formula that shows the numbers and types of of each element in a compound.

Question 13

What are structural isomers?

Answer 13

Compounds with the same molecular formula but different structural formulae.

Question 14

What are stereoisomers?

Answer 14

Organic compounds with the same molecular formula and structural formula but different arrangements of atoms in space.

Question 15

What is cis-trans isomerism?

Answer 15

A type of E/Z isomerism in which the two substituent groups attached to both carbon atoms of the C=C bond are the same.

Question 16

What is E/Z isomerism?

Answer 16

A type of stereoisomerism caused by the restricted rotation around the double bond. Two different groups are attached to both carbon atoms of the C=C bond.

Question 17

How do you identify the E/Z isomers using CIP rules?

Answer 17

1) Locate C=C bond and redraw it to show substituents
2) Assign the priority of each substituent based on its RAM
3) If the highest priority groups are on the same side of the C=C, then the isomer is Z and if they are on opposite sides then the isomer is E.

Question 18

What are reaction mechanisms?

Answer 18

Models that show the movement of electron pairs during a reaction.

Question 19

What do curly arrows show?

Answer 19

The flow of electron pairs in reaction mechanisms.

Question 20

What is homolytic fission?

Answer 20

When each bonding atom receives one electron from the bonded pair, forming two radicals.

Question 21

What is heterolytic fission?

Answer 21

When one bonding atom receives both electrons from the bonding pair.

Question 22

What are radicals?

Answer 22

Species with one or more unpaired electrons.

Question 23

What are alkanes?

Answer 23

A homologous series of unsaturated hydrocarbons.

Question 24

What two factors affect the boiling points of alkanes?

Answer 24

Carbon chain length and branching.

Question 25

Why does boiling point increase as carbon chain length increases?

Answer 25

There are more surface area contacts between adjacent molecules in larger alkanes. This increases the number of induced dipole-dipole forces, so more energy is needed to overcome these forces.

Question 26

Why is the boiling point of branched hydrocarbons lower than non-branched ones?

Answer 26

Molecules cannot fit together as neatly when branched. This reduces the amount of surface area contact. This means they have fewer dipole-dipole interactions and therefore less energy is needed to overcome the forces of attraction.

Question 27

What is complete combustion?

Answer 27

Oxidising a fuel in a plentiful supply of air.

Question 28

What is incomplete combustion?

Answer 28

Oxidising fuel in a limited supply of air.

Question 29

Where is a σ bond formed?

Answer 29

Between two carbon atoms using the direct overlap of electron clouds of the two atoms.

Question 30

Where is a π bond formed?

Answer 30

In adjacent p-orbitals overlapping above and below the carbon atoms.

Question 31

What are monomers?

Answer 31

Small molecules that are used to make polymers.

Question 32

What are polymers?

Answer 32

Macromolecules made from small repeating units.

Question 33

What is a repeating unit?

Answer 33

A specific arrangement of atoms that occurs in a structure over and over again.

Question 34

What ways can plastics be disposed of?

Answer 34

• Landfill
• Combustion
• Combustion with electrical generation
• Reusing
• Recycling
• Use as organic feed-stock

Question 35

What is a bioplastic?

Answer 35

A material made from a renewable source that is biodegradable.

Question 36

What are biodegradable material?

Answer 36

A material that is affected by the action of microorganisms and environmental conditions, leading to decomposition.