4.2 Flashcards

1
Q

primary alcohol

A

one carbon is attached to the carbon bonded to the OH

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

secondary alcohol

A

2 carbons are attached to the carbon bonded to the OH

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

tertiary alcohol

A

3 carbons are attached to the carbon bonded to the OH

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

what’s the oxidising agent for alcohols and what happens to it

A

acidified potassium chromate, its reduced and the alcohol is oxidised

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

what are primary alcohols oxidised to if the oxidation is carried out under distillation

A

primary alcohols to aldehydes

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

what are primary alcohols oxidised to if the oxidation is reflux

A

primary alcohols to carboxylic acids

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

definition of reflux

A

heating chemicals strongly) while cooling the vapour into a liquid using a condenser

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

what are secondary alcohols oxidised to

A

to form ketones

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

are tertiary alcohols oxidised in these conditions

A

no

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

what does tollens reagent, fehlings solution and *k2Cr2O2/H2SO4 oxidise a aldehyde to

A

aldehyde to carboxylic acid

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

what does [O] mean

A

oxidising agent

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

what happens when a primary alcohol is oxidised twice

A

in equation its 2[O] and the primary alcohol is oxidised into a carboxylic acid.

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

with oxidation of alcohols what do you use to oxidise them

A

acidified potassium dichromate

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

in order to vigorously oxidise something, what do u do

A

use reflux

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

to get an aldehyde from a primary alcohol, what do u do

A

distil

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

what do u do for:

  • primary alcohol to aldehyde
  • primary alcohol to carboxylic acid
A
  • distil

- reflux

17
Q

what are haloalkanes

A

alkanes with halogen atoms

18
Q

talk about the bond in haloalkanes and what does this mean

A
  • the bond is polar

- the delta + carbon is deficient thus can get attacked by a nucleophile

19
Q

whats a nucleophile and what are some examples

A

an electron pair donor- it could be a negative ion or atom with a lone pair of electrons
OH-, CN- and NH3. water is a weak nucleophile

20
Q

halogenoalkanes can be hydrolysed to make alcohols, what type of reaction is this

A

nucleophilic substitution

21
Q

halogenoalkanes can be hydrolysed to make alcohols, what compounds are needed for this reaction to take place

A

a warm aqueous alkali, e.g sodium hydroxide or potassium hydroxide

22
Q

which halogenoalkanes are hydrolysed the slowest

A

fluoroalkanes hydrolyse the slowest as they have the strongest bonds

23
Q

describe the test used to highlight the rate of reaction with haloalkanes- 2-iodopropane, bromoalkene, chloroalkane

A
  • mix haloalkane with water (a nucleophile so nucleophilic sub takes place) to form an alcohol
  • put in silver nitrate so the silver will react with the halide.
  • heat in waterbath
  • yellow precipitate form quickly with 2-iodopropane so iodoalkanes are most reactive
  • bromoalkenes react slower and chloroalkanes react the slowest- both form a white precipitate
24
Q

what are CFCs

A

chlorofluorocarbons

  • contain only fluorine, chlorine and carbon
  • they’re very stable, volatile, non flammable and non toxic
  • scientists discovered they’re destroying the ozone layer
25
how is ozone formed naturally
when an oxygen molecule is broken down into two free radicals by uv radiation, the free radicals attack other oxygen molecules forming ozone O2---UV-->O+O---->O2+O-->O3
26
why are holes in the ozone layer forming
because CFCs in the upper atmosphere absorb UV radiation and split to form chlorine free radicals- they destroy ozone molecules and regenerate to destroy more ozone
27
draw the mechanism of CFCs destroying ozone. | also draw the overall mechanism
``` E.G CF2CL2----uv---> •CF2CL+•CL main mechanism: Cl•+O3--->O2+CLO• CLO•+O-->O2+CL• (the O radical comes from the breakdown of oxygen buy UV) -overall reaction- O3+O-->2O2 (Cl• is the catalyst) ```
28
what can also break down ozone apart from CFCs
Nitrogen oxides
29
draw the mechanism for nitrogen oxides breaking down the ozone. also draw the overall mechanism
O3+•NO---->O2+•NO2 •NO2+O--->•NO+O2 (the O radical comes from the breakdown of oxygen buy UV) O3+O-->2O2