4.1 Basic Concepts and Hydrocarbons

Question 1

What are aliphatic hydrocarbons?

Answer 1

In which the carbon atoms are joined together in straight unbranched chains or branched chains.

Question 2

What are alicyclic hydrocarbons?

Answer 2

Carbon atoms joined together in ring structure.

Not aromatic

Question 3

What are aromatic hydrocarbons?

Answer 3

At least one benzene ring in the structure.

Question 4

What is nomenclature.

Answer 4

Naming system for compounds.

Question 5

What are alkanes?

Answer 5

A homologous series of saturated hydrocarbons

Question 6

What happens when you remove a hydrogen atom from an alkane?

Answer 6

And alkyl group is formed.

Question 7

General formula for alkanes?

Answer 7

CnH2n+2

Question 8

What is the general formula for alkenes?

Answer 8

CnH2n

Question 9

What is the formula for alcohols?

Answer 9

CnH2n+1OH

Question 10

What’s an isomer?

Answer 10

Same molecular formula but different arrangements of atoms.

Question 11

What are stereoisomers?

Answer 11

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

Question 12

Define reaction mechanism

Answer 12

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

Question 13

What are curly arrows for?

Answer 13

Model the flow of electron pairs during reaction mechanism

Question 14

What is homolytic fission?

Answer 14

When each bonding atom receives one electron from the bonded pair, forming two radicals.
Fission = bond breaking
Bonded our split EQUALLY

Question 15

What are radicals?

Answer 15

A species with one or more unpaired electrons

Question 16

What is heterolytic fission?

Answer 16

When one bonding atom receives both electrons from the bonding pair

Question 17

What happens to the boiling point of an alkane as chain length increases?

Answer 17

Boiling point increases due to larger molecular mass, larger surface area and larger dipole dipole forces.

Question 18

What happens to the boiling point of alkanes as branching increases?

Answer 18

Lower boiling points due to fewer surface area interactions, fewer induced dipole dipole

Question 19

Define complete combustion

Answer 19

Oxidising a fuel in a plentiful supply of air

Question 20

Define incomplete combustion

Answer 20

Oxidising a fuel in a limited supply of air

Question 21

What are alkenes?

Answer 21

A homologous series of unsaturated hydrocarbons.

Question 22

What is an electrophile?

Answer 22

An electron pair acceptor

Question 23

What is needed for hydrogenation?

Answer 23

A temperature of 150 and a suitable catalyst.

Question 24

What can halogenation be used for?

Answer 24

A test for saturation.

Question 25

What does the process of hydration require?

Answer 25

High temperatures and high pressures with a phosphoric acid catalyst

Question 26

What is a reaction mechanism?

Answer 26

A model that shows the movement of electrons in an organic reaction.

Question 27

What happens with a hydrogen halide is added to an unsymmetrical alkene?

Answer 27

There are two possible products.

Question 28

What does markownikoffs rule state?

Answer 28

When H-X is added to an unsymmetrical alkene, the hydrogen becomes attached to the carbon with the most hydrogen atoms to start with.

Question 29

Method one monitoring hydrolysis of haloalkanes

Answer 29

AgNO3 Water bath and ethanol 40-80C Relative rate of precipitation

Question 30

Method two monitoring hydrolysis haloalkanes

Answer 30

AgNO3 NaOH NEUTRALISE WITH HNO3 Relative amount of precipitation

Question 31

Uses for CFCs other than propellants

Answer 31

Fire extinguishers decreasing agents Dry cleaning Blowing polystyrene

Question 32

Why are branched alkanes better for fuel?

Answer 32

More efficient combustion

Question 33

How can environmental damage be reduced when dealing with polymers?

Answer 33

``` Making bio or photodegradable polymers Develop ways of sorting AND recycling Use as chemical feedstock by cracking Make from plant based chemicals Use a higher atom economy ```

Question 34

Define homologous series

Answer 34

A series of compounds with the same functional group and each successive member differing by -CH2

Question 35

What metals are in a catalytic converter?

Answer 35

Platinum, rhodium and palladium are thinly spread over a mesh

Question 36

What happens in catalytic converters

Answer 36

Gasses pass over the catalyst

Question 37

Reactions in catalytic converter?

Answer 37

2CO + O2 = 2CO2 | 2NO + 2CO = CO2 + N2

Question 38

What type of forces there there between alkane chains?

Answer 38

London force

Question 39

Why are alkanes not reactive to electrophiles and nucleophiles?

Answer 39

Carbon and hydrogen have similar electronegativities and sigma bonds are hard to break