NEET Practice Questions (MCQs) with Answers & Solutions

The NCERT text states, 'Amines are classified as primary (1o), secondary (2o) and tertiary (3o) depending upon the number of hydrogen atoms replaced by alkyl or aryl groups in ammonia molecule. If one hydrogen atom of ammonia is replaced by R or Ar, we get $RNH_2$ or $ArNH_2$, a primary amine (1o).'

The NCERT text provides an example: '$CH_3NHCH_2CH_3$ is named as N-methylethanamine'. This directly matches the given structure for the question.

The NCERT text states, 'In IUPAC system, primary amines are named as alkanamines. The name is derived by replacement of ‘e’ of alkane by the word amine. For example, $CH_3NH_2$ is named as methanamine.'

Table 9.1 in the NCERT context lists '$CH_3–CH_2–CH_2–NH_2$' with the common name 'n-Propylamine' and IUPAC name 'Propan-1-amine'.

The NCERT text states, 'To name secondary and tertiary amines, we use locant N to designate substituent attached to a nitrogen atom. For example, $CH_3 NHCH_2CH_3$ is named as N-methylethanamine...'

Table 9.1 in the NCERT context lists 'Hexamethylenediamine' with the IUPAC name 'Hexane-1,6-diamine'.

The NCERT text states, 'Amines are said to be ‘simple’ when all the alkyl or aryl groups are the same, and ‘mixed’ when they are different.'

Table 9.1 in the NCERT context lists 'Trimethylamine' with the IUPAC name 'N,N-Dimethylmethanamine'.

The NCERT text mentions, 'Two biologically active compounds, namely adrenaline and ephedrine, both containing secondary amino group, are used to increase blood pressure.'

Propan-2-amine ($CH_3CH(NH_2)CH_3$) has only one alkyl group attached to the nitrogen, making it a primary amine. N-Methylethanamine ($CH_3CH_2NHCH_3$) and N,N-Dimethylethanamine ($CH_3CH_2N(CH_3)_2$) are secondary and tertiary amines respectively. Trimethylamine ($(CH_3)_3N$) is a tertiary amine.