Arrange the following in the correct order of their acidic strength.

The number of nucleophiles in the following list is

$$ \mathrm{CH}_3 \mathrm{NH}_2, \mathrm{CH}_3 \mathrm{CHO}, \mathrm{C}_2 \mathrm{H}_4, \mathrm{CH}_3 \mathrm{SH} $$

From the following identify the groups that exhibit negative resonance $(-R)$ effect when attached to conjugated system

$$ \begin{array}{ccccc} \text { Formyl } & \text { Amino } & \text { Alkoxy } & \text { Cyano } & \text { Nitro } \\ A & B & C & D & E \end{array} $$

Identify the ortho and para-directing groups towards aromatic electrophilic substitution reactions from the following list

$$\mathrm{\mathop { - OH}\limits_I \mathop { - CN}\limits_{II} \mathop { - C{O_2}H}\limits_{III} \mathop { - OC{H_3}}\limits_{IV} \mathop { - NHCOC{H_3}}\limits_V \mathop { - CHO}\limits_{VI}}$$

The compound or ion which is not aromatic in the following is

Arrange the following in decreasing order of their pK_b values

A. ,$$\mathrm{CH}_3 \mathrm{NH}_2$$

B. $$(\mathrm{CH}_3)_3 \mathrm{~N}$$

C.

D.

Which compound among the following is most reactive towards electrophilic reagents?

Which of the following is not explained by hyperconjugation?

Identify the product of the following reaction.

The following effect is known as