Carboxylic Acids Flashcards
What allows carboxylic acids to form hydrogen bonds with water molecules?
The polar C=O and OH bonds in carboxylic acids
This polarity enables solubility in water.
Up to how many carbon atoms are carboxylic acids typically soluble in water?
Four carbon atoms
Beyond this, solubility decreases due to the non-polar carbon chain.
What effect does an increasing number of carbon atoms have on the solubility of carboxylic acids?
Solubility decreases
The non-polar carbon chain affects the overall polarity of the molecule.
What type of acids are carboxylic acids classified as?
Weak acids
They partially dissociate in water.
What is the simplest carboxylic acid?
Methanoic acid (HCOOH)
It contains only one carbon atom.
What is the dissociation equation for methanoic acid in water?
HCOOH(aq) = H+(aq) + HCOO-(aq)
This shows the partial dissociation of the acid.
What types of reactions do carboxylic acids undergo?
Redox and neutralisation reactions
They react with metals and bases.
What happens when carboxylic acids react with metals?
They form hydrogen gas and carboxylate salts
The metal disappears, and effervescence occurs.
What is the product of the reaction between propanoic acid and magnesium?
(CH3CH2COO-)2Mg2+(aq) + H2(g)
This illustrates the formation of carboxylate salt and hydrogen gas.
What do carboxylic acids produce when they react with bases?
A salt and water
This is an example of neutralisation.
What is the reaction of ethanoic acid with sodium hydroxide?
CH3COOH(aq) + NaOH(aq) → CH3COO-Na+(aq) + H2O(l)
This forms sodium ethanoate and water.
What gas is evolved when a carboxylic acid reacts with a carbonate?
Carbon dioxide (CO2)
If the carboxylic acid is in excess, the solid carbonate disappears.
What is the reaction of ethanoic acid with sodium carbonate?
2CH3COOH(aq) + Na2CO3(aq) → 2CH3COO-Na+(aq) + H2O(l) + CO2(g)
This illustrates the products of the reaction.
What is a common method to distinguish carboxylic acids from other organic compounds?
The neutralisation reaction with carbonates
Carboxylic acids are the only common organic compounds that react with carbonates.
True or False: Phenols are acidic enough to react with carbonates.
False
Carboxylic acids are the only common organic compounds that react with carbonates.
