When ethyl amine is heated with chloroform and alcoholic $KOH$,a compound with an offensive smell is obtained. This compound is

Nitration of aniline also gives $m$-nitroaniline in a strong acidic medium because:

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$: Experimental reaction of $CH_{3}Cl$ with aniline and anhydrous $AlCl_{3}$ does not give $o-$ and $p-$methylaniline.
Reason $(R)$: The $-NH_{2}$ group of aniline becomes deactivating because of salt formation with anhydrous $AlCl_{3}$ and hence yields $m-$methylaniline as the product.
In the light of the above statements,choose the most appropriate answer from the options given below.

Arrange the following amines in the order of increasing basicity.

Consider the molecule $1,3-dimethyl-1,2,3,4-tetrahydroquinoxaline$ with an amino group at the $5$-position. Upon protonation,which nitrogen atom is the most basic and will be protonated first? Identify the correct structure of the product '$A$' formed after protonation.

Hoffmann bromamide degradation of benzamide gives product $A$,which upon heating with $CHCl_{3}$ and $NaOH$ gives product $B$. The structures of $A$ and $B$ are