Carboxylic Acids Flashcards
as chain length of carboxylic acid increases, solubility decreases, why?
- carboxyl group is polar and forms hydrogen bonds with H2O
- hydrocarbon chain is non-polar and does not form hydrogen bonds
- larger proportion of the molecule is non-polar as hydrocarbon group increases
describe the chemical test for a carboxylic acid
- add sodium carbonate solution
- acid present if effervescence occurs
what is produced when a carboxylic acid and metal react
salt + hydrogen
what is produced when a carboxylic acid and carbonate react
salt + water + carbon dioxide
what is produced when a carboxylic acid and alkali react
salt + water
what are the reagents and conditions for carboxylic acid + alcohol (esterification)
reagents: carboxylic acid + alcohol
conditions: concentrated H2SO4 catalyst and heat
what type of reaction is an esterification
condensation reaction
it is reversible and so the yield of ester obtained is relatively low
what is the equation for saponification of a tryglyceride
tryglyceride + NaOH = glycerol + soap
what is biodiesel
a renewable non-petroleum based fuel that is mainly formed using vegetable oils reacting with methanol, by acid or base catalysed transesterification
what is the problem with biodiesel
the likelihood that farmers will stop planting food and start to plant crops that favour biodiesel production instead - leading to a food shortage
what is hydrolysis
hydrolysis is the breaking of a covalent bond by its reaction with water
what are the reagents, conditions and products of acid-catalysed hydrolysis of an ester
reagents: aqueous acid (H2SO4)
conditions: heat under reflux
products: alcohol + carboxylic acid
what are the reagents, conditions and products of base-catalysed hydrolysis of an ester
reagents: aqueous alkali (NaOH)
conditions: heat under reflux
products: alcohol + salt of the carboxylic acid (sodium …)
name 2 derivatives of carboxylic acid
- acyl chlorides
- acid anyhdrides
