What's in a Medicine Flashcards
1
Q
Give the general formula of alcohols.
A
ROH
2
Q
Give the general formula of aldehydes.
A
RCOH
3
Q
Give the general formula of ketones.
A
RCOR’
4
Q
Give the general formula of carboxylic acids.
A
RCOOH
5
Q
Give the general fromula of acid anhydrides.
A
(RCO)2O
6
Q
Give the general formula of esters.
A
RCOOR’
7
Q
Give the general formula of ethers.
A
ROR’
8
Q
Give the structural formula of alcohols.
A
R-OH
9
Q
Give the structural formula of aldehydes.
A
R-C=O
|
H
10
Q
Give the structural formula of ketones.
A
R-C-R
||
O
11
Q
Give the structural formula of carboxylic acids.
A
O
||
R-C-O-H
12
Q
Give the structural formula of acid anhydrides.
A
O O
|| ||
R-C-O-C-R’
13
Q
Give the structural formula of esters.
A
R
|
C=O
|
O
|
R
14
Q
Give the structural formula of ethers.
A
R-O-R
15
Q
Prefix/suffix of alcohols
A
-ol
16
Q
Prefix/suffix of aldehydes
A
-al
17
Q
Prefix/suffix of ketones
A
-one
18
Q
Prefix/suffix of carboxylic acids
A
-oic acid
19
Q
Prefix/suffix of acid anhydrides
A
-oic anhydride
20
Q
Prefix/suffix of esters
A
-oate
21
Q
Prefix/suffix of ethers
A
-oxy-
22
Q
Describe primary alcohols.
A
When in -OH is attached to a carbon bonded to only one carbon.
23
Q
Describe secondary alcohols.
A
When the -OH is attached to a carbon bonded to 2 carbons.
24
Q
Describe tertiary alcohols.
A
When the -OH is attached to a carbon bonded to three carbons.
25
What is the structure of a phenol?
OH group attached to a benzene ring.
26
What is the test for phenols?
Addition of iron(III) chloride. Solution turns purple.
27
Describe the acidic nature of phenols.
Weak acids so partially dissociate in water to form a phenoxide ion and a H+ ion.
28
Describe the reaction of phenols with alkalis.
React to form salt + water
29
Describe the reaction of phenols with carbonates.
don’t react
eg. sodium carbonate is not a stong enough base to remove the hydrogen ion from phenol
30
phenols - how to tell them apart from carboxylic acids
carboxylic acids react with carbonates (and alkalis) and give off CO2 gas
phenol doesn’t react with carbonates
phenol doesn’t give off CO2 when react with alkali
31
Describe the reaction of phenols with acid anhydrides.
React to form an ester and a carboxylic acid.
32
phenols - how to tell them apart from alcohols
* alcohols react with carboxylic acids to make an ester and water
* phenols do not react with carboxylic acids to form an ester
* (both form an ester and carboxylic acid when reacting with acid anhydride)
33
Describe the reaction of alcohols with carboxylic acids.
React to form esters - esterification reaction
* heat carboxylic acid and alcohol with an acid catalyst (conc. sulfuric/hydrochloric acid)
* form an ester and water
34
Describe the reaction of alcohols with acid anhydrides.
alcohol + acid anhydride –> ester + carboxylic acid
35
State the possible products from the oxidation of alcohols.
* carbonyl compounds (ketone and aldehyde)
* carboxylic acid
need to use the oxidising agent acidified potassium dichromate(VI)
36
Describe the oxidation of primary alcohols.
primary alcohol –> aldehyde –> carboxylic acid
37
Describe the oxidation of secondary alcohols.
secondary alcohol –> ketone
38
Describe the oxidation of tertiary alcohols.
Cannot be oxidised by dichromate - only by burning
39
Describe the oxidation process of primary alcohols.
can control how far the reaction goes
1. gently heat with potassium dichromate(VI) and sulfuric acid in a flask produces an ALDEHYDE
- to get just the ALDEHYDE need to get it out of the oxidising agent - DISTILLATION APPARATUS
(the aldehyde boils at a lower temp. than the alcohol so evaporates and is distilled off immediately)
2. to produce CARBOXYLIC ACID needs to be vigorously oxidised
- alcohol mixed with excess oxidising agent and heated UNDER REFLUX
40
Describe the oxidation process of secondary alcohols.
under reflux using acidified potassium dichromate(VI)
41
Describe the possible methods for dehydration of alcohols.
1. Ethanol vapour is passed over a hot **solid** catalyst of pumice stone or aluminium oxide, Al2O3 - the catalyst provides a large surface area for the reaction.
2. reflux with excess concentrated sulfuric acid catalyst or phosphoric acid at 170 degrees C.
42
Decribe process of dehydrating alcohols using hot catalyst method.
mineral/ ceramic wool is soaked in ethanol, pumice stone or Al2O3 is heated, the alkene gas collects in an inverted cylinder in a water bath.
43
Decribe the process of dehydrating alcohols using reflux method.
* heat solution in a flask fitted with a vertical Liebig condenser - this causes the solution to continuously boil/evaporate and then condense back into the flask, giving it time to react
* heat solution electronically; hot plates, heating mantles.
44
Decribe the formation of haloalkanes.
Formed via substitution reaction of alcohols and halide compounds e.g. HCl. The -OH group is replaced by the halide (other product is made of the OH lost and what’s left of the halogen)
45
Define elimination reaction.
The removal of a molecule from a saturated molecule to make an unsaturated molecule.
46
How do you make an alkene from alcohol?
Make an alkene by eliminating water from an alcohol in a dehydration reaction.
47
Mass spectra - what does it tell us?
helps identify compounds
relative atomic mass
relative molecular mass
relative isotopic abundance
molecular structure
48
Mass spectra - how does it work?
1. vapourisation - the sample is turned into a gas by an electrical heater
2. ionisation - the gas particles are bombarded with high energy electrons to ionise them. Electrons are knocked off the particles leaving +ve ions
3. acceleration - the +ve ions are accelerated by an electric field
4. detection - the time taken for the +ve ions to reach the detector is measured. This depends on an ion’s mass and charge. Lighter, highly charged ions first.
49
mass spectra - what is the M+ peak?
gives the relative molecular mass of a compound
the mass/charge value is the molecular mass
its the far right peak
50
mass spectra - what is the M+1 peak?
a smaller peak to the right of the molecular ion peak
51
mass spectra - what causes the M+1 peak?
caused by the presence of the carbon isotope 13C
52
mass spectra - describe fragmentation
the bombarding electrons make some of the molecular ions break up into fragments
- the fragments the are ions show up on the mass spectrum making a fragmentation pattern
53
mass spectra - what is fragmentation used for?
used to identify molecules and their structure
54
mass spectra - how do you work out structural formula?
1. work out what ion could have made each peak from its m/z value
2. identify the fragments
3. piece them together to form a molecule with the correct Mr
55
infrared spectra - how does it work?
1. a beam of infrared radiation is passes through a sample of a chemical
2. the IR radiation is absorbed by the covalent bonds in the molecules
- this increases their vibrational energy (they vibrate more)
3. bonds between different atoms absorb different frequencies of IR radiation and bonds in different places in a molecule also absorb different frequencies
eg. O-H bond in alcohol and O-H bond in carboxylic acids absorb different frequencies
56
infrared spectra - what does it tell us?
An infrared spectrometer produces a spectrum that shows you what frequencies of radiation the molecules are absorbing
can use this to identify the functional groups in a molecule
also means that you can tell if a functional group has changed during a reaction.
