In aqueous solution, basicity depends on the availability of the lone pair on the nitrogen atom for protonation. Dimethylamine is the strongest base, followed by methylamine, trimethylamine, and ammonia.
Thus, the correct order of basicity is (A).
Which of the following amines does not give foul smell of isocyanide on heating with chloroform and ethanolic KOH ?
Amines are usually formed from amides, imides, halides, nitro compounds, etc. They exhibit hydrogen bonding which influences their physical properties. In alkyl amines, a combination of electron releasing, steric and H-bonding factors influence the stability of the substituted ammonium cations in protic polar solvents and thus affect the basic nature of amines. Alkyl amines are found to be stronger bases than ammonia. Amines being basic in nature, react with acids to form salts. Aryldiazonium salts, undergo replacement of the diazonium group with a variety of nucleophiles to produce aryl halides, cyanides, phenols and arenes.