2. You are given a sample containing three organic compounds: a hydrocarbon (RH)
ID: 791342 • Letter: 2
Question
2. You are given a sample containing three organic compounds: a hydrocarbon (RH), carboxylic
acid (RCOOH), and an amine (RNH2, organic compound with acid-base properties similar tammonia).
All of these compounds are very soluble in ether and insoluble in water. Using a flow chart, show
how you could separate the components of this mixture using extraction.
You are given a sample containing three organic compounds: a hydrocarbon (RH), carboxylic acid (RCOOH), and an amine (RNH2, organic compound with acid-base properties similar tammonia). All of these compounds are very soluble in ether and insoluble in water. Using a flow chart, show how you could separate the components of this mixture using extraction.Explanation / Answer
If the carboxylic acid, amine were dissolved in the hydrocarbon, then use a series of aqueous extractions.
A dilute acidic aqueous solution should not dissolve in the hydrocarbon mixture, but would dissolve the organic amine.
RNH2 (or) + H+ (aq) ---> RNH3+ (aq)
A 10% aqueous NaHCO3 solution could then be used to extract the carboxylic acid.
RCOOH (or) + NaHCO3 (aq) ---> RCOONa (aq) + H2O (l) + CO2 (g)
leaving nothing but the hydrocarbon.
(aq) means dissolved in water
(or) means dissolved in an organic solvent (in this case the hydrocarbon).