Uses of Amines
Amines Worksheet
1. The compound N-trimethyl-N-dodecylammonium chloride can be used as a cationic surfactant.
a) State the meaning of the term surfactant.
Surfactants are molecules that decrease the surface tension between two phases where at least one of the phases is liquid (two liquids, a liquid and a gas, or a liquid and a solid).
b) Draw the skeletal formula for a N-trimethyl-N-dodecylammonium ion.
c) Explain how the N-trimethyl-N-dodecylammonium ion behaves as a surfactant.
The charged head of the molecule (the ammonium group) is hydrophilic. It can form ionic interactions between the positive charge on the nitrogen and the partially negative oxygen atoms on water molecules.
The dodecyl tail is hydrophobic (non-polar) and interacts with other non-polar molecules (like oil) using Van der Waals forces.
This amphiphilic nature allows the ions to surround droplets of oil, forming micelles, which allows the oil to disperse in water.
2. The molecule 1-amino-5-nitrobenzene has several uses.
a) Draw a molecule of 1-amino-5-nitrobenzene.
b) State the main use for this substance.
It is used to make azodyes, a type of dye used extensively in the textile and food industries.