Functional groups Flashcards
What are primary, secondary and tertiary alcohols oxidised to?
Primary alcohols to aldehydes/ carboxylic acids
secondary alcohols to ketones
tertiary alcohols can’t be oxidised
Why are alcohols polar?
Because oxygen is more electronegative than hydrogen so electrons are pulled closer to oxygen resulting in an uneven distribution.
Why do alcohols have a higher mp than alkanes?
Alcohols have forces AND hydrogen bonding. Alkanes have no hydrogen bonding.
What is the symbol for a thiol group?
SH
Is sulphur more or less electronegative than oxygen?
Less electronegative
What is the functional group of ethers and do they have a higher or lower bp than alcohols?
R-O-R
lower bp
When two thiol groups react in an oxidation what type of bond is created?
Disulphide bond
What is a thioether and give an example of a common one?
Sulfur atom connected to two alkane chains
methionine- essential amino acid
What is the difference between a ketone and an aldehyde?
A ketone has a double bond to an oxygen in the middle of the chain whereas aldehydes have double bonds to oxygen at the end of the chains
Can aldehydes and ketones form hydrogen bonds?
Only with water
Do carboxylic acids have a high or low mp?
Very high mp as they form hydrogen bonds
How are esters formed and do they form hydrogen bonds?
Condensation of a carboxylic acid an alcohol.
The H of the carboxyl group is replaced so hydrogen bonding is eliminated.
What is the difference between an ester and a thioester?
In a thioester, an oxygen from the ester is replaced with a S
What are the structures of primary, secondary and tertiary amines?
primary - R-N-H
|
H
secondary - R-N-H
|
R
tertiary - R-N-R
|
R
What affects the bp of amines?
The number of hydrogen bonds to the amine
What are the structures of the primary, secondary and tertiary amides?
Primary - R-C=O
|
H-N-H
Secondary - R-C=O
|
H-N-H
Tertiary - R-C=O
|
R-N-R
Describe the strength of amines compared to their corresponding alcohol and amides compared to their corresponding carboxyl group
Amines are weaker than their corresponding alcohol.
Amides are stronger than their corresponding carboxyl group.
