Dimethylamine (CH3)NH has a molecular weight of 45 and a boiling point of 7.4 C. Trimethylamine (CH3)3N has a higher molecular weight but a lower boiling point of 3.5 C. Explain this apparent discrepancy

NO HyDROGEN BONDING IN TERTIARY AMINES

Physical Properties of Compounds of Amines
Amines are organic compounds that include a nitrogen atom with a lone pair of electrons in the functional group. They are ammonia derivatives in which one or more hydrogen atoms are substituted by alkyl or aryl substituent groups. Some important amines include amino acids, biogenic amine, trimethylamine, and aniline.
Lower aliphatic amines have a fishy odor and are gaseous in nature. At normal temperature, primary amines with three or four carbon atoms are liquids, whereas those with more are solids.
Lower aliphatic amines are soluble in water because they may establish hydrogen bonds with water molecules. The molar mass of amines increases as the size of the hydrophobic alkyl portion grows, resulting in a decrease in its solubility in water. Higher amines are water-insoluble. As a result of hydrogen bonding between the nitrogen of one molecule and the hydrogen of the other, primary and secondary amines frequently form intermolecular associations. Due to the presence of two hydrogen atoms in primary amines, intermolecular interaction is more significant than in secondary amines. Due to the lack of a free hydrogen atom for bonding, there is no intermolecular interaction in tertiary amines. The boiling points of amines are in the following order: Primary, secondary, and tertiary.
Amines, phosphines, and pyridines are all high-boiling liquids or solids that are flammable at room temperature but not exceedingly so. Methylamine is an exception, as it is a gas with a wide range of flammability. The burning of amines produces noxious NOx fumes.