Question

What is the basis for classifying amines as primary, secondary or tertiary
A. The number of carbon atoms bonded directly to the nitrogen atom
B. The number of carbon atoms bonded to a carbon-bearing nitrogen
C. The number of nitrogen atoms present
D. The number of hydrogen atoms present

Answer 1

To answer this question, you should recall the concept of nomenclature of amines. Amines are the chemical species with one or more atoms of nitrogen.

Complete step by step answer:
The nitrogen in ammonia is similar to the nitrogen in amines as nitrogen can bond up to three hydrogens. Although the carbon connected to nitrogen affects its chemical properties. In the case of amines, the carbon atoms bonded to the nitrogen atom are counted.
By this way, we can classify amines as primary, secondary, or tertiary according to the number of carbons bonded directly to the nitrogen atom. The simplest amine i.e. in case of primary amines only one carbon is bonded to the nitrogen atom. In case of secondary amines, two carbon atoms are bonded to the nitrogen atom, and tertiary amines have three carbons bonded to the nitrogen.

Hence, the correct option is A.

Note:
Unlike ammonia, amines act as bases with few of them with strong basicity. In case of resonating amines, the lone pair which is present over nitrogen in the amine group is "drawn in" towards this delocalisation and this interaction makes the lone pair less available to bond to an incoming hydrogen ion. More electrons are available around nitrogen as ethyl is an electron-donating group. Lone pair of electrons on nitrogen is involved in delocalisation. This is the reason that amines are basic. Nomenclature of amines: Oldest and most typically used alkane series naming system is to classify every cluster connected to the gas atom so add the ending-amine, as in methylamine $:C{H_3}N{H_2}$; N-ethyl-N-propylamine: $C{H_3}C{H_2}NHC{H_2}C{H_2}C{H_3}$. Numerous fragrant amines and most cyclic amines have unimportant names that might be utilized as a parent to assign the other associated. According to the Guidelines set by IUPAC, the nomenclature of compounds must follow these steps:
-The Longest Chain Rule
-The Lowest Set of Locants
-Multiple instances of the same substituent
-The naming of different substituents
-Correct naming of different substituents in case they are present at the same positions
-Naming Complex Substituents