In the given reaction,$[X]$ will be:

Which of the following cyclic amines has the lowest $\Delta G^{o}$ for inversion?

Aniline in a set of the following reactions yielded a coloured product $Y$.
Aniline $\xrightarrow[(273-278 \ K)]{NaNO_{2}/HCl} X$ $\xrightarrow{N,N-dimethylaniline} Y$
The structure of $Y$ would be

The correct statement regarding the basicity of arylamines is

What is obtained when aniline hydrogen sulfate is heated with sulfuric acid at $453 - 473 \, K$?

The chemical reaction shown in the image represents the reduction of a diazonium salt to an aromatic hydrocarbon. Identify the reagent typically used for this transformation.