Dr. S.N. DHAWAN, Dr. S.C.KHETERPAL and, P.N.KAPIL Solutions for Chapter: Organic Chemistry - Some Basic Principles and Techniques, Exercise 4: Competition Focus

Sodium fusion extract, obtained from aniline, on treatment with iron $\left(\mathrm{II}\right)$ sulphate and ${\mathrm{H}}_2{\mathrm{SO}}_4$ in presence of air gives a Prussian blue precipitate. Hence, the blue colour is due to the formation of.

How many of the following are heterocyclic aromatic compounds? 

Benzene, cyclopentadiene, oxirane, tetrahydrofuran, naphthalene, cyclopentane, tropolone, azulene, diphenyl. 

Total number of alkyl groups having the molecular formula ${\mathrm{C}}_4{\mathrm{H}}_9$ is.

How many of the following cannot show tautomerism? 

Acetophenone, acetaldehyde, cyclohexanone, acetylacetone, benzoquinone, acetone, benzaldehyde, butanone, ethyl acetoacetate. 

The total number of cyclic isomers possible for the hydrocarbon with molecular formula ${\mathrm{C}}_4{\mathrm{H}}_6$ is?

Amongst the following the total number of electrophiles is :

${\mathrm{CN}}^{-}, {\mathrm{H}}^{+}, {{\mathrm{NO}}_2}^{+}, {\mathrm{Cl}}^{+},{\mathrm{OH}}^{-}, {\mathrm{H}}_3{\mathrm{O}}^{+}, :{\mathrm{CH}}_2, :{\mathrm{NH}}_3, {\mathrm{Na}}^{+}$

Amongst the following the total number of nucleophiles is :

${\mathrm{SO}}_3, {{\mathrm{NH}}_2}^{-}, {\mathrm{R}}^{-}, {\mathrm{H}}_2\mathrm{O}, {\mathrm{OR}}^{-}, \mathrm{ROH}, {\mathrm{AlCl}}_3, {\mathrm{H}}^{-}, {\mathrm{BF}}_3$ 

The total number of contributing structures showing hyperconjugation (involving $\mathrm{C}-\mathrm{H}$ bonds) for the carbocation given on R.H.S. is.