Carbonyl compounds undergo nucleophilic addition because of 

1. The electrophilic carbonyl carbon forms a sigma bond with the nucleophile.

2. Electromeric effect.

3. Electronegativity difference of carbon and oxygen atoms.

4. None of the above

Carboxylic acids are more acidic than phenol and alcohol because of 

1. formations of dimers

2. highly acidic hydrogen

3. resonance stabilization of their conjugate base

4. intermolecular hydrogen bonding 

Acetaldehyde cannot exhibit

1. Iodoform test

2. Benedict's test

3. Lucas test

4. Tollen's test

Ketones$\left({\mathrm{R}}_1{\mathrm{COR}}_2\right)$; ${\mathrm{R}}_1={\mathrm{R}}_2=$alkyl groups, can be obtained in one step by:

1. hydrolysis of esters

2. oxidation of primary alcohols

3. oxidation of secondary alcohols

4. reaction of acid halides and alcohols

The product formed by the reaction of chlorine with benzaldehyde in the absence of catalyst is

1. benzoyl chloride

2. benzyl chloride

3. chlorobenzene

4. o-chlorobenzaldehyde

The precipitate formed on heating ethanal with Fehling's solution is:

Monomer of trioxane is

1. formaldehyde

2. acetone

3. isoprene

4. acetaldehyde

Which will not give formaldehyde on heating or up distillation?

1. paraldehyde

2. trioxane

3. formalin

4. paraformalehyde 

Given the following reaction:
CH₃CHO+HCN→X
(Assume compound X has a chiral centre)
The optical activity associated with product X would be: 

1. Laevorotatory 
2. Dextrorotatory
3. Mesocompound
4. Racemic mixture

Benzophenone can be converted into benzene using 

1. anhydrous ${\mathrm{AlCl}}_3$

2. acidified dichromate

3. sodium amalgam in water

4. fused alkali