26.3- CARBOXYLIC ACIDS AND ESTERS Flashcards
(22 cards)
What is the functional groups of carboxylic acids?
-COOH
How many functional groups do carboxylic acids have and what are they?
two
carbonyl group C=O
hydroxy group -OH
As the two functional groups of carboxylic acids are on one carbon atom, what happens?
changes properties of each group
What is the most obvious different of the change in properties of each group as the two functional groups are on one carbon atom?
-OH group in carboxylic acids much more acidic than -OH group in alcohols
What suffix is used to name carboxylic acids?
-oic acid
When there are substituents or side chains on the carbon chain, how are they names?
counting from carbon of carboxylic acids as carbon number one
When the functional group -COOH is attached to a benzene ring, how is named?
suffix -carboxylic acids used + carbon of functional group NOT counted as part of root
What type of bond can the carboxylic acid group form with water molecules?
hydrogen bonds
As the carboxylic acid group can form hydrogen bonds with water molecules, what does this mean?
carboxylic acids, up to and including, four carbons completely soluble in water
When else do carboxylic acids form hydrogen bonds other than with water molecules?
with one another in solid state
As carboxylic acids can hydrogen bond with one another when in solid state. what are their melting point like in comparison to alkanes of similar relative molecular mass?
have much higher melting points than alkanes of similar relative molecular mass
What is one way of identifying a carboxylic acid?
measure its melting point + compare it with tables of known melting points
What can be used to find the melting point of a carboxylic acid?
Thiele tube or can be found electrically
What is pure ethanoic acid sometimes called?
glacial ethanoic acid
Why is ethanoic acid sometimes called glacial ethanoic acid?
may freeze on cold day- its freezing point is 13°C
What are esters derived from?
carboxylic acids
How is an ester derived from a carboxylic acid?
hydrogen (from -OH group of acid) replaced by hydrogen group- alkyl or aryl group (OH replaced by OR)
How is an ester named?
based on parent acid but name always being with alkyl group that has replaced hydrogen of acid
How volatile are shorter chain esters and what is their smell like?
fairly volatile + have pleasant fruity smells
As shorter chain esters are fairly volatile + have pleasant fruity smells, what are they used in?
flavourings + perfumes
What are shorter chain esters also used as other than flavourings + perfumes?
solvents + plasticisers
What are fats and oils in terms of esters?
esters with longer carbon chains
