Chapter 6 --organic Chemistry

Question 1

Functional group

Answer 1

In a molecule is an atom or group of atoms that gives the compound some distinctive and predictable properties

Eg. COOH - gives molecules a sour acidic taste

Question 2

Homologous series

Answer 2

Set of compounds with the same functional group, similar chemical properties and physical properties - show graduation / gradual change from one to the next

Question 3

Alcohols

Answer 3

-OH

ol ending for hydroxyl group

Question 4

Chain isomerism

Answer 4

Structural isomerism

Same molecular formular but different structure eg

CH3-CH2-CH2-CH3

CH3-CH-CH3
|
CH3

Question 5

Position isomerism

Answer 5

Molecules with same functional group but attached in different positions on the same carbon chain

Eg. propan-1-ol , propan-2-ol

Question 6

Stereoisomerism

Answer 6

Have same molecular formular

Same structural formular

Different arrangement

Question 7

Fractional distillation

Answer 7

Converts crude oil into a small number of fractions

Done in a distillation Column

Question 8

Cracking

Answer 8

Demand for shorter chained hydrocarbons is higher.

Passing hydrocarbons in heavier fractions through a heated catalyst (zeolite usually — which is aluminium,silicon, oxygen)
One large molecule —> at least two smaller molecules

Question 9

Reforming

Answer 9

Straight chained allanes burn less efficiently than branches chained /rings (cyclic compounds)

Converts straight chained alkanes into branched/cyclic hydrocarbons by heating them with a catalyst (platinum)
Helps them burn more smoothly in the engine

Question 10

Inside catalytic converters

Answer 10

2CO + O2 —> 2CO2

2NO + 2CO —> N2+2CO2

Question 11

Biodiesel

Answer 11

Vegetable oils

Question 12

Bioethanol

Answer 12

Bacteria made rather than enzymes —- eg corn

Question 13

Comparing fuels 4

Answer 13

Land use
Yield / speed
Manufacture n transport
Carbon neutrality

Question 14

Radical

Answer 14

Species with an unpaired electron

Question 15

Mechanism

Answer 15

Sequence of two or more steps (with each, an equation) that shows how a reaction takes place

Question 16

Test for Alkene

Answer 16

Decolourises bromine water

Question 17

Hydration catalyst

Answer 17

Phosphoric Acod

H3PO4

Question 18

Diol

Answer 18

Compound containing two -OH groups

Question 19

Oxidation to diols

Answer 19

Oxidising agent - potassium manganate(VII)

Acidic conditions (usually dilute sulfúrico acid)

Potassium manganate(VII) provides oxygen atom and water in solution provides another and 2* Hydrogen atoms

KManganate from purple to colourless (can be used like bromine water to test for alkene)

Question 20

Ketone

Answer 20

When a secondary alcohol is oxidised - homologous series

Question 21

Ketone formula

Answer 21

RCOR

Question 22

Aldehyde

Answer 22

When a primary alcohol is oxidised

Question 23

Aldehyde formula

Answer 23

RCHO

Question 24

Aldehyde oxidised further

Answer 24

Gain of oxygen atom not loss of hydrogen

Carboxylic acid

Question 25

Carboxylic acid formula

Answer 25

RCOOH

Question 26

Usual reagent for oxidation reactions primary and secondary alcohols

Answer 26

Mixture of potassium dichromate(VI) and dilute sulfúric acid

Question 27

Ketone ending

Answer 27

-one

Question 28

Aldehyde ending

Answer 28

-al

Question 29

Heating under reflux

Answer 29

When oxidation intended to be complete Products stay in reaction ( boil off but condense in vertical condenser n return to heating flask)

Question 30

Distillation with addition

Answer 30

When oxidation intended to be incomplete - to obtain an aldehyde- Only oxidising agent heated and alcohol slowly added to oxidising agent Aldehyde distils off immediately when formed as has much lower boiling point than alcohol used to make it - aldehyde collected in reciever

Question 31

Why thermometer in distillation

Answer 31

If temp remains steady then indicates one compound is distilling over If temp rises after a while , indicates a diff compound is distilling over

Question 32

Pros of simple distillation over fractional

Answer 32

Easier to set up and quicker

Question 33

Cons of simple distillation over fractional

Answer 33

Doesn’t separate liquids as well Should only be used if boiling temp of liquid being purified is very diff from other liquids in mixture (more than 25^C)

Question 34

Immiscible

Answer 34

Doesn’t mix

Question 35

Testing for purity

Answer 35

Measure boiling temp of liquid Error may be thermometer Diff organic compounds have same boiling temp

Question 36

Homolytic fission

Answer 36

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

Question 37

Hydration

Answer 37

Adding H and OH to C=C Usually heat Allene with steam and pass mixture over catalyst of phosphoric acid.

Question 38

Oxidation to diols

Answer 38

Oxidising agent = potassium manganite (VII) Acid conditions - dilute sulfuric acid Use [O] as oxidising agent

Question 39

Heterolytic fission

Answer 39

Formation on ions as a result Both electrons go to one atom eg. In H-Br when bond breaks , electrons to bromine as it is more electronegative than H

Question 40

Electrophilic addition

Answer 40

Electrophilic - species accepts a pair of electrons from another species and forms a covalent bond Addition - two molecules react to form a single molecule

Question 41

Nucleophile

Answer 41

Species with a lone pair of electrons Forms a covalent bond with a + charges atom