Tag: chemistry

Questions Related to chemistry

Which of the following doesn't use acetaldehyde as a starting material in its preparation?

  1. Ethyl acetate

  2. Ethanoic acid

  3. Methanoic acid

  4. Drugs


Correct Option: C
Explanation:
Methanoic acid needs only single carbon compound  not acetaldehyde.
$HCOOH$-formic acid/Methanoic acid.

Which of the following is used for preserving biological specimens?

  1. Formaldehyde

  2. Ether

  3. Ethyl alcohol

  4. None of these


Correct Option: A
Explanation:

Formaldehyde ($HCHO$) in the form of formalin (40% solution of formaldehyde) is used for preserving biological specimens.

Formaldehyde is used :

  1. for preserving biological specimens

  2. for the preparation of urotropine

  3. in the manufacture of bakelite

  4. all of these


Correct Option: D
Explanation:

Formaldehyde is used for preserving specimens for the preparation of Urotropine and in manufacture of Bakelite.

Benzaldehyde is used:

  1. as a flavouring agent for food

  2. in the manufacture of triphenylmethane dyes like malachite green

  3. as a starting material for the preparation of cinnamic acid

  4. all of these


Correct Option: D
Explanation:

Benzaldehyde is used as flavoring agent, manufacture of dyes like triphenylmethane dyes and also as starting material for the preparation of cinnamic acid.

Which of the following statement is true?

  1. Benzaldehyde is used in perfumery industry

  2. Formaldehyde is used for silvering mirrors

  3. Acetone is used as a commercial solvent

  4. All of the above


Correct Option: D
Explanation:
A. Benzaldehyde is used in perfumery
B. Formaldehyde is used for silvering mirrors because of its aldehydic group.
C. Acetone is used as a commercial solvent for the various organic compound.

Formalin is _______ % solution of formaldehyde in water

  1. 10

  2. 20

  3. 40

  4. 60


Correct Option: C
Explanation:
Formalin is $40$% solution of formaldehyde in water.
Formalin means $40$% formaldehyde.

Which of the following is the flavouring agent for food, beverages etc?

  1. Acetone

  2. Formaldehyde

  3. Benzaldehyde

  4. Phenol


Correct Option: C
Explanation:
Benzaldehyde is used as flavoring, perfumery and in dye industries.
So, benzaldehyde is flavoring agent for food and beverages.

Which of the following can be used as a solvent for cellulose acetate, cellulose nitrate, and celluloide?

  1. Formaldehyde

  2. Acetaldehyde

  3. Acetic acid

  4. Acetone


Correct Option: D
Explanation:
Acetone is most used industrial solvent, for many synthetic fibers. It is good solvent for synthetic fibres as it is denaturant and it reduces explosive reactions.

Acetone is used:

  1. for extraction of essential oils

  2. as a constituent of liquid nail polish

  3. both A and B

  4. none of these


Correct Option: C
Explanation:

Acetone is used for extraction of essential oils and a constituent of liquid nail polish. Also. It is used in perfumes as it causes aroma.

Butyraldehyde are produced commercially by:

  1. hydroformylation

  2. hydroacetylation

  3. formylation

  4. acetylation


Correct Option: A
Explanation:
Hydroformylation is an industrial process for the formation aldehydes from Alkenes also called as oxo-synthesis
Butyraldehyde also produced commercially from Hydroformylation.