carboxylic acid + alcohols Flashcards
what type of functional group is in a carboxylic acid?
carboxyl functional group (-COOH)
what is the general formula of a carboxlic acid?
CnH2n+1COOH
what is the structural formula of methanoic acid?
HCOOH
what is the structural formula of ethanoic acid?
CH3COOH
what is the structural formula of propanoic acid?
C2H5COOH/CH3CH2COOH
what is the structural formula of butanoic acid?
C3H7COOH / CH3CH2CH2COOH
why do the boiling points of carboxylic acids increase down the series?
as the molecules become larger and heavier, the molecular size of alkanes increases and the intermolecular forces of attraction between molecules increases -> more energy is required to overcome the intermolecular forces ofa ttraction between the molecules
what is the trend of carboxlic acids’ solubility in water?
as the length of the hydrocarbon chain increases, the solubility decreasees
what state of matter are the first four carboxylic acids?
liquids at room temperature
why are carboxylic acids weak acids?
they dissociate/ionise partially in water to produce hydrogen ions (RCOOH -><- RCOO- + H+)
how do carboxylic acids react with reactive metals?
carboxylic acids + reactive metal -> salt + hydrogen
how do carboxylic acids react with bases?
(neutralisation) carboxylic acid + base -> salt + water
how do carboxylic acids react with carbonates?
carboxylic acid + metal carbonate -> carbon dioxide + water + salt
what is the reaction that creates esters?
carboxylic acid + alcohol -> ester + water
what are the conditions that form esters from carboxylic acids and alcohols?
alcohol with concentrated sulfuric acid as catalyst + heat (under reflux)
why does concentrated sulfuric acid need to be used to form esters?
catalyses the reaction + helps to shift the position of equilibirum to the right as it removes water
where is ethanoic acid used?
as a flavouring + preservative in food
how can u make ethanoic acid from ethanol?
oxidiation with acidified KMNO4 or acidified K2Cr2O7 and heat under reflux / oxidation by atmospheric oxygen
what does acidified potassium manganate (VII) do in ethanoic acids production?
it acts as an oxidising agent and is reduced + colour changes from purple to colourless
what does acidified potassium dichromate (VI) do in ethanoic acids production?
acts as an oxidising agent and is reduced + colour changes from orange to green
what does ethanol do in ethanoic acids production?
it acts as a reducing agent and is oxidised to ethanoic acid
what is the reaction of ethanol’s oxidation?
CH3CH2OH (l) + 2(O) -> (heat) CH3COOH (aq) + H2O (l)
what is the equation of oxidation by atmospheric oxygen?
CH3CH20H (l) + O2 (g) -> (bacteria) CH3COOH (aq) + H2O (l)
what is an ester?
formed between carboxylic acid + alcohol
what is the generla formula for an ester?
CnH2nO2
what is the functional group of esters
-COO-
what are some physical properties of esters?
colourless and volatiel liquids + possess pleasant smell
what is the trend of esters being soluble in water?
small esters are soluble in water, but solubility decreases with increase in molecular size -> most esters are insoluble in water
what are the uses of esters?
used in food flavouring + manufacure perfumes + as solvents for cosmetics and glues + in soaps
what is esterification?
when an ester is formed when a mixture of an aolchol and a carboxylic acid is warmed together with a few drops of concntrated sulfuric acid
what are the conditions of esterification?
heating under reflux + concentrated sulfuric acid as a cata;lyst
what type of reactions are esterification?
condensation reaction + reversible reaction
how are esters name?
from alcohols: make name into an alkyl form
from carboxylic acid: replace the ‘-ic acid’ with ‘-ate’
how are esters name?
from alcohols: make name into an alkyl form
from carboxylic acid: replace the ‘-ic acid’ with ‘-ate’
