Flashcards in Carboxylic Acids and Amines Deck (20):
What state do carboxylic acids exist in?
Solids or liquids
What happens as the chain length of a carboxylic acid increases?
Hydrogen bonding diminishes
Why are carboxylic acids able to form dimers?
Because they can form hydrogen bonds
When are dimers unable to exist?
When in aqueous solution of carboxylic acids
What happens as the chain length of a carboxylic acid increases with respect to solubility?
As the chain length of the carboxylic acid increases water solubility decreases
What does the equal bond length (between single and double bond) between the two C-O bonds suggest?
Electrons are delocalised over the carbon and two oxygen atoms. This provides the carboxylate ion with some stability.
How can oxidisation be used to prepare carboxylic acids?
Oxidising an aldehyde with acidified potassium dichromate under reflux.
How can you prepare carboxylic acids using hydrolysation?
By hydrolysing esters, amides or nitriles by heating them under reflux with either an acid or alkali catalyst
What do carboxylic acids form salts with?
What is the reaction between ammonia and carboxylic acids?
Forms ammonium salts (subsequent heating produces amides)
What is the reaction between carboxylic acids and amines?
What is the effect of the very strong reducing agent, lithium aluminium hydride and the carboxylic acid?
It is reduced directly to the primary alcohol
What are amines?
Organic derivatives of ammonia in which one or more hydrogen atoms in ammonia has been replaced by an alkyl group.
What is a tertiary amine?
When three of the hydrogens have been replaces by alkyl groups.
What is CH3CH2NHCH3?
Why do primary and secondary amines have higher boiling points than tertiary amines?
Because they can form hydrogen bonds between their molecules
What is the solubility of amines?
Primary, secondary and tertiary amines of short chain length can dissolve in water. Tertiary amines form H bonds with water because of their lone pair of electrons.
How do amines form alkaline solutions?
The nitrogen accepts a proton from the water molecule, generating alkyl ammonium ions and hydroxide ions.
What is the reaction between amines and mineral acids?