1/2O-Intro To Organic And Alkanes

Question 1

What’s a homologous series

Answer 1

Series of compounds containing the same functional group (atoms causing molecules to have similar chemical properties)
Gradual change in physical properties
Each member differs by CH2

Question 2

What’s general formula

Answer 2

Algebraic formula for a homologous series

Question 3

What’s structural formula

Answer 3

Shows arrangement of atoms in a molecule (structure around each carbon)

Question 4

What’s displayed formula

Answer 4

Shows all the bonds and atoms present in a molecule

Question 5

What’s skeletal formula

Answer 5

Organic formula contains carbon skeleton where each point represents a carbon.

Question 6

IUPAC rules

Answer 6

Practise questions in purple booklet

Question 7

IUPAC prefixes

Answer 7

2- di
3- tri
4- tetra
5- pent
6-hex

Question 8

What’s the functional group of an alkane

Answer 8

CnH2n+2

Question 9

What’s the functional group of alkenes

Answer 9

C=C

Question 10

What’s the functional group of halo/halogeno alkanes

Answer 10

Has F,Cl,Br,I atom in it

Question 11

What’s the functional group of an alcohol

Answer 11

-OH

Question 12

What’s the functional group of an aldehyde

Answer 12

H-C=O
(Hydrogen bonded to carbon)

Question 13

What’s the functional group of a ketone

Answer 13

C-C=O
(Carbon bonded to the rest of an alkane chain)

Question 14

What’s the functional group of a carboxylic acid

Answer 14

C=O
|
OH

Question 15

What’s an isomer

Answer 15

Molecules with the same molecular formula but the atoms are arranged differently

Question 16

What are the 3 types of structural isomerism

Answer 16

Positional
Functional group
Chain

Question 17

What’s positional isomerism

Answer 17

Functional group is attached to main chain at different points
eg 1-chloropropane (chlorine on carbon 1)
And
2-chloropropane (chlorine in carbon 2)

Question 18

What’s functional group isomerism

Answer 18

A molecular formula could represent molecules with different functional groups
eg C2H6O could form an alcohol or an ether

Question 19

What’s chain isomerism

Answer 19

The hydrocarbon chain is arranged differently (branches)

Question 20

Are alkanes saturated or unsaturated hydrocarbons

Answer 20

Saturated

Question 21

What’s petroleum

Answer 21

Mixture consisting mainly of alkanes

Question 22

How can a mixture of hydrocarbons be separated and what does it form

Answer 22

Fractional distillation, fractions form depending on the boiling point of the hydrocarbons

Question 23

What’s cracking

Answer 23

Breaks C-C bonds in long alkane chains

Question 24

What are the conditions needed for thermal cracking

Answer 24

High pressure
High temps
Produces a high percentage of alkenes

Question 25

What are the conditions needed for catalytic cracking

Answer 25

Slight pressure High temps Zeolite catalyst Produces motor fuel and aromatic hydrocarbons

Question 26

Why is it economical to crack hydrocarbons

Answer 26

Cracking produces shorter hydrocarbon chains which are more useful and in demand, this means demand can be met

Question 27

What are alkanes used for

Answer 27

Fuels

Question 28

How do alkanes and organic compounds combust

Answer 28

Completely and incompletely under high temperatures

Question 29

What do catalytic converters do

Answer 29

Remove nitrogen oxides, carbon monoxide, carbon and unburned hydrocarbons from internal combustion engines

Question 30

What does the combustion of hydrocarbons containing sulphur produce

Answer 30

Sulphur dioxide causing air pollution

Question 31

How is sulphur dioxide removed from flue gases with calcium oxide or calcium carbonate

Answer 31

Calcium oxide/carbonate slurry and water sprayed into flue gas neutralising it forming calcium sulphite, oxidised into calcium sulphate (gypsum) to be used in plaster or plasterboard

Question 32

What’s a free radical

Answer 32

A reactive species which possesses and unpaired electron Represented with a dot

Question 33

What are the steps of a free radical mechanism

Answer 33

Initiation, molecule turned into two radicals Br2 —> 2Br• Propagation, molecule + radical (formed in initiation) —> radical + molecule, then radical (formed from eq above) + molecule —> radical + molecule CH4 + Br• —>CH3• + HBr CH3• + Br2 —> Br• + CH3Br Termination, radical + radical —> molecule Br• + Br• —> Br2 CH3• + CH3• —> C2H6 CH3• + Br• —> CH3Br Practise Qs

Question 34

Conditions for free radical substitution

Answer 34

Initiation requires uv light

Question 35

What type of isomerism is E-Z and how does it occur

Answer 35

Stereoisomerism Due to restricted rotation about the planar C=C double bond (found in alkenes) Two different groups attached to each C atom

Question 36

What is stereoisomerism

Answer 36

Same structural formula but different spatial arrangement of atoms

Question 37

What are the priority rules when naming E-Z isomers

Answer 37

Look at each carbon, the atom attached to each carbon with the highest atomic number gets circled If these molecules are on the same side they are [Z] If they are on opposite sides they are [E]