Organic Chemistry 6 Flashcards

1
Q

formula for benzene

A

C6H6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how are the 6 carbons in benzene arranged?

A

in a ring structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how many electrons does each carbon have in its outermost shell

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what happens to the 3 of the 4 electrons in carbon’s outer shell

A

form sigma bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 sigma bonds formed by carbon’s electrons

A

2 formed between each carbon atom

1 between carbon and hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what shape do these electrons give benzene

A

planar hexagonal ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

where is the 1 electron that is left

A

in a p orbital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

describe what happens to the p orbitals

A

the lobes of these p orbitals fuse to form a single ring of charge above and below the sigma bond skeleton. these are pi bonds. electrons can move around - delocalised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does the delocalisation of electrons cause

A

causes bonds in benzene to be similar and makes the molecule unexpectedly stable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the bonds in benzene

A

not single and not double, but an intermediate between the two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

which type of reaction would benzene typically undergo?

A

substitution reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what would one might expect to be benzene’s usual reaction type and why

A

addition reactions as it is unsaturated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

is benzene a polar or non-polar molecule and why?

A

non-polar as the centres of positivity coincide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

is benzene soluble in water and why

A

no as it is non-polar and does not form hydrogen bonds with water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what did benzene used to be used for and why not anymore

A

as an organic solvent but no longer as it is carcinogenic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is now used in benzene’s place as an organic solvent

A

methylbenzene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

some aromatic pharmaceuticals

A

aspirin, morphine, paracetamol, penecillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

aromatic dye

A

napthalene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

some aromatic narcotics

A

heroin and cocaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

aromatic insecticide

A

DDT

21
Q

aromatic disinfectant

A

TCP

22
Q

aromatic material

A

terylene is a type of polyester

23
Q

aromatic indicator

A

phenolphthalein

24
Q

some aromatic fragrant oils

A

menthol and clove oil

25
Q

EXTRACTION OF CLOVE OIL

main constituent of clove oil

A

eugenol

26
Q

EXTRACTION OF CLOVE OIL

principle of steam distillation

A

when two immiscible liquids are together, their boiling point is lower than either of the two pure compounds alone

27
Q

EXTRACTION OF CLOVE OIL

2 immiscible liquids

A

oil and water

28
Q

EXTRACTION OF CLOVE OIL

if you did not mix with water

A

would have to bring cloves up to the oil’s boiling point and would char the clove and would become impossible to extract the oil

29
Q

eugenol

top

A

OH

30
Q

eugenol

first right C

A

OCH3

31
Q

eugenol bottom

A

C-H
C-H
H-C-H

32
Q

EXTRACTION OF CLOVE OIL
if oil doesn’t form a separate layer
solvent extraction

A

droplet dispersed - emulsion
organic solvent dissolves oil and then separated from water using separating funnel
organic solvent evaporates off

33
Q

EXTRACTION OF CLOVE OIL

safety precaution

A

wear gloves as oil can burn the skin

34
Q

EXTRACTION OF CLOVE OIL

first step

A

add water to steam generator

35
Q

EXTRACTION OF CLOVE OIL

explain the safety tube

A

placed in the steam generator, bottom should be well below level of water. water topped up regularly. relieves pressure, avoids build up of steam and explosion

36
Q

EXTRACTION OF CLOVE OIL

where do you put the cloves

A

in the pear shaped flask with some water

37
Q

EXTRACTION OF CLOVE OIL

cloves are in

A

bunsen burner turned on and steam allowed to pass through for 40 minutes

38
Q

EXTRACTION OF CLOVE OIL

what happens to the clove oil emulsion

A

passed through the condenser to the receiver (separating funnel)

39
Q

EXTRACTION OF CLOVE OIL

describe the emulsion

A

milky colour

40
Q

EXTRACTION OF CLOVE OIL

what happens to emulsion

A

allowed to cool

41
Q

EXTRACTION OF CLOVE OIL

what is added to emulsion

A

organic solvent e.g.cyclohexane added and contents of separating funnel shaken vigorously

42
Q

EXTRACTION OF CLOVE OIL

before separating emulsion

A

invert the funnel and tap to release pressure

43
Q

EXTRACTION OF CLOVE OIL

how do you extract

A

draw off the clear aqueous lower layer into a beaker labelled aqueous and repeat the process many times with the organic layer

44
Q

EXTRACTION OF CLOVE OIL

why do you repeat many times

A

to maximise the yield of oil collected

45
Q

EXTRACTION OF CLOVE OIL

where do you then place the organic layer

A

in a beaker, it may contain some water

46
Q

EXTRACTION OF CLOVE OIL

what do you add to the organic layer in the beaker and how much? what happens?

A

add enough anhydrous sodium sulfate so that it no longer clumps together
it should appear to settle as a dry powder when all of the water has been removed from the clove oil

47
Q

EXTRACTION OF CLOVE OIL

after adding anhydrous sodium sulfate

A

swirl flask and filter to remove drying agent, rinse with cyclohexane to maximise yield of oil

48
Q

EXTRACTION OF CLOVE OIL

last step

A

the cyclohexane solvent was allowed to evaporate off from the filtrate in a warm place or desiccator. This leaves the clove oil behind, measure its volume.