Complete the following reaction: C 6 H 5 CHO → H 2 NCONHNH 2 ?

Aldehyde and ketones react with semicarbazide NH 2 NH . CONH 2 to form semicarbazone. It is a nucleophilic addition reaction. C 6 H 5 CHO Benzaldehyde → H 2 NCONHNH 2 C 6 H 5 - CH = N . NH . CONH 2 Benzaldehyde semicarbazone + H 2 O Water This test is used for identification and characterisation of aldehydes and ketones.

HARD

Earn 100

The correct statement/s about the following reaction sequence is/are:

50% studentsanswered this correctly

Important Questions on Aldehydes, Ketones and Carboxylic acids

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

The product formed by the reaction of an aldehyde with a primary amine is:

HARD

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

The test performed on compound

x

and their inferences are:

Test	Inference
$(a)$ $2, 4$ - $D N P$ test	Coloured precipitate yellow
$(b)$ Iodoform test	Yellow precipitate
$(c)$ Azo-dye test	No dye formation

Compound $' x'$ is:

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Give balanced equation for benzaldehyde reacts with hydrazine.

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Reaction of a carbonyl compound with one of the following reagents involves nucleophilic addition followed by elimination of water. The reagent is:

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

C_{6} H_{5} {NH}_{2} + C_{6} H_{5} CHO \to C_{6} H_{5} N = {CHC}_{6} H_{5}

involves

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

How will you obtain Urotropine from formaldehyde? (Give chemical equations only).

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Give balanced chemical equations for the following reactions: Acetone reacts with phenyl hydrazine

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

{NH}_{3}

and its derivative do not show nucleophilic addition reactions with aldehydes and ketone in high acidic medium. Justify.

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Which one of the following compounds will give orange precipitate when treated with

2, 4 -

dinitrophenyl hydrazine ?

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

The number of nitrogen atoms in a semicarbazone molecule of acetone is_____

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

How will you obtain Acetone hydrazone from acetone? (Give chemical equations only).

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

An organic compound

A

with molecular formula

C_{7} H_{6} O

forms

2, 4 - DNP

derivative and reduces Tollens' reagent. When

A

is heated with conc.

KOH

, it gives sodium benzoate and compound

B

. The compound

B

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

How will you obtain Urotropine (Hexamethylene tetra-amine ) from formaldehyde? (write only chemical equation).

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

What happens when acetaldehyde is treated with hydrazine?

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Complete the following reaction:

$C_{6} H_{5} CHO \overset{H_{2} {NCONHNH}_{2}}{\to} ?$

HARD

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Benzoic acid on reaction with

{SOCl}_{2}

gives (A). (A) on reduction with

Pd - {BaSO}_{4}

H_{2}

in presence of quinoline affords (B). (B) reacts with

{NH}_{2} OH, HCl

in presence of

{CH}_{3} COONa

in aqueous ethanol to furnish (C). (C) on reaction with

{PCl}_{5}

gives (D). Write the structures of (A), (B), (C) and (D). What is the role of

{CH}_{3} COONa

in the conversion of (B) to (C)?

EASY

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Draw structure of cyclopropanone oxime.

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Which among the following is correct structure of the semicarbazone formed when ethanal reacts with semicarbazide?

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

A compound

C_{5} H_{10} O (A)

forms a phenylhydrazone and gives negative Tollen's test and a positive Iodoform reaction. It also gives

n

-pentane on reduction. The compound

(A)

MEDIUM

Chemistry>Organic Chemistry>Aldehydes, Ketones and Carboxylic acids>Reactions of aldehydes and ketones

Formaldehyde on reaction with ammonia gives a compound

A

, which is on nitration yields cyclonite. The compound

A

The correct statement/s about the following reaction sequence is/are:

Important Questions on Aldehydes, Ketones and Carboxylic acids

Learn and Prepare for any exam you want !