Which of the following carbocation is most stable?

(a) \((CH_3)_3 C.C^{+}H_2\)

(b) \( (CH_3)_3\; C^{+}\)

(c) \( CH_3 CH_2C^{+}H_2\)

(d) \( CH_3 C^{+}HCH_2CH_3\)

Indicate the σ and π bonds in the molecules: CH₃NO₂

The reaction:

\(CH_3 CH_2 I+KOH_{(aq)} \rightarrow CH_3 CH_2 OH +KI\) is classified as :

(a) electrophilic substitution

(b) nucleophilic substitution

(c) elimination

(d) addition

The best and latest technique for isolation, purification and separation of organic compounds is:

(a) Crystallisation

(b) Distillation

(c) Sublimation

(d) Chromatography

In the Lassaigne’s test for nitrogen in an organic compound, the Prussian blue colour is obtained due to the formation of:

(a) \( Na_4[Fe(CN)_6]\)

(b) \( Fe_4[Fe(CN)_6]_3\)

(c) \( Fe_2[Fe(CN)_6]\)

(d) \( Fe_3[Fe(CN)_6]_4\)