15C.2 Flashcards
how can we obtain carboxylic acid using oxidation
by oxidizing a primary alcohol or aldehyde using potassium dichromate(VI) and heat under reflux (with primary alcohol first forming an aldehyde) then fractionally distill the reaction mixture to obtain a purse sample of carboxylic acid
what is the oxidation reaction for aldehydes and primary alcohols into carboxylic acid
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what are nitriles
organic compounds containing the CN group
what are the two ways you can obtain pure carboxylic acid
- oxidation of an aldehyde or a primary alcohol with a potassium dichromate (VI) heating under reflux
- hydrolysis of a nitrile by heating under reflux with dilute acid or aqueous alkali
how can we get a carboxylic acid from hydrolysis
by heating a nitrile under reflux with either a dilute acid or a aqueous alkali and the carboxylic acid is distilled through fractional distillation, where the C N triple bond breaks and nitrogen from ammonia or an ammonium ion ( note with aq alkali a carboxylate ion is formed but that can be formed in a carboxylic acid by just adding dilute acid)
what are the hydrolysis reactions of nitriles
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what are the four main reactions that carboxylic acid undergoes
- reduction
- neutralization
- halogenation
- esterification
what does the reduction of carboxylic acids from
primary alcohol
why doesn’t the reduction of carboxylic acid from aldehyde
because aldehydes are more easily reduced compared to carboxylic acid so any aldehyde formed during the reaction will be immediately reduced to a primary alcohol
what is the reducing regent used in reduction of carboxylic acid
lithium aluminium hydride LiAlH4 and is used in a solvent of dry ether
what is the reduction equation for reduction of carboxylic acid
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how can we neutralized a carboxylic acid
even through there week acids they can be completely neutralized using aq alkali
what are the products of neutralization of carboxylic acid
carboxylate salt and water
what are the uses of sodium ethanoate
- hand warmers
- additive that give the salt and vinegar flavor for potato chips
what is the equation of the neutralization of sodium ethanoate
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what are the carboxylate salt general formula
RCOONa and since there ionic it can be RCOO^-Na^+
how does the halogenation of carboxylic acid occurs
the OH group is replaced by a halogen forming acyl chlorides (COCl), HCl, and phosphorus trichloride oxide (POCl) which is a liquid that mixes with the the acyl so we use fractional distillation to get the acyl
what are acyl chlorides
they are highly reactive organic compounds made from the halogenation of carboxylic acids and they have the functional group of COX
what is the regent used in the halogenation of carboxylic acids
phosphorus(V) chloride ( phosphorus pentachloride)
why do we carry out halogenation of carboxylic acids in anhydrous conditions
because both the regent and the product of acyl chloride can react with water
why is heating not required in halogenation of carboxylic acids
because it is a very vigorous reaction
what is the suffix for acyl chloride
oyl chloride
what is the chemical equation for that halogenation of carboxylic acids
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what happens during esterification
carboxylic acid reacts with alcohol and a small amount of acid catalyst (often concentrated sulfuric acid) to form an ester and water
even with a catalyst esterification is
slow and reversible
what are the uses of esters
- solvents
- make polymers (polyesters)
- responsible for the smells of fruit
- most animal fats
- most vegetable oil
how do we name an ester
first is the alkali group from the alcohol then the carboxylate from the carboxylic acid for example ethyl methanoate
what is the chemical equation for esterification
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