Tag: chemistry

Questions Related to chemistry

Nitrobenzene is used for making aniline, an important chemical used in:

chemistry organic nitrogen compounds nitroarenes- preparation and properties nitro compounds types of organic reactions

  1. the making of glue

  2. the dyeing industry

  3. the crimping of wool

  4. fast-drying varnish

Show answer
Correct Option: B
Explanation:
Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine. Its main use in dyeing industry is as a precursor to indigo, the blue of blue jeans.

A compound X of formula $\displaystyle C _{2}H _{5}NO _{2}$ on treatment with $\displaystyle (HNO _{2}+HCl)$ gives off an inactive gas Y and form Z when heated with soda lime X gives A $\displaystyle (CH _{5}N)$ soluble in acid Find the true statements among the following.

chemistry organic nitrogen compounds nitroarenes- preparation and properties nitro compounds types of organic reactions

  1. A answers carbylamine test

  2. X is an amino acid

  3. Y is $\displaystyle CO _{2}$

  4. Z is a hydroxyl acid

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Correct Option: B,D

The percentage of formaldehyde in formalin is:

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. $40$%

  2. $30$%

  3. $20$%

  4. $10$%

Show answer
Correct Option: A
Explanation:
The percentage of formaldehyde in formalin is $40$%
$10$ml formalin contains $40$ ml formaldehyde and $60$ ml of water.

Which of the following is used as a food preservative?

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Aldehydes

  2. Ketones

  3. Carboxylic acid

  4. Alcohol

Show answer
Correct Option: C
Explanation:

Carboxylic acid used as food preservatives.

Sodium Benzoate (salt of Benzoic acid) is used as food preservatives.

Which of the following aldehyde is mostly used as plasticizer?

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Formaldehyde

  2. Acetaldehyde

  3. Butyraldehyde

  4. Benzaldehyde

Show answer
Correct Option: C
Explanation:

Butyraldehyde is used as an intermediate in the manufacturing of plasticizer.

Hence, option C is correct.

Which is the commercially largest produced aldehyde?

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Acetaldehyde

  2. Formaldehyde

  3. Benzaldehyde

  4. Butyraldehyde

Show answer
Correct Option: B
Explanation:

Of all aldehydes, formaldehyde is produced on the largest scale, about 6,000,000 tons per year.

Formalin is:

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. $60$% solution of formaldehyde

  2. $40$% solution of formaldehyde

  3. $30$% solution of formaldehyde

  4. $50$% solution of formaldehyde

Show answer
Correct Option: B
Explanation:
Formalin is the composition of $40$% formaldehyde,
$60$% water. Hence formalin is $40$% formaldehyde.

Which of the following aldehyde is very much used in perfumery and in dye industries?

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Formaldehyde

  2. Acetaldehyde

  3. Benzaldehyde

  4. Butyraldehyde

Show answer
Correct Option: C
Explanation:

Benzaldehyde is much used perfumery industries because it has bitter almond odor and also it is used for making aniline dye.

Which of the following does not uses formaldehyde in its preparation?

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Melamine polymer

  2. Bakelite

  3. PHBV

  4. preservation of biological specimens

Show answer
Correct Option: C
Explanation:

Formaldehyde is not used in the preparation of PHBV. PHBV is a thermoplastic polymer. The monomers, 3-hydroxybutanoic acid and 3-hydroxypentanoic acid, are joined by ester bonds; the back bone of the polymer is made up of carbon and oxygen atoms.

A major constituent of vinegar is:

chemistry aldehydes, ketones and carboxylic acids uses of aldehydes and ketones organic compounds with functional group containing oxygen (part-2) carbonyl compounds

  1. Methanoic acic

  2. Benzoic acid

  3. Ethanoic acid

  4. Picric acid

Show answer
Correct Option: C
Explanation:

The main constituent of vinegar is acetic acid. The other constituents will depend on the nature of the raw material that has undergone fermentation.

Hence, option $C$ is correct.