
$C_2H_2\xrightarrow[1% \ HgOH]{H_2SO_4}A\overset{[O]}{\rightarrow}B$, B is
A. An acid
B. An aldehyde
C. A ketone
D. Ethanol
Answer
164.1k+ views
Hint: In the presence of hot dilute sulfuric acid and mercury (I) hydroxide, alkynes add a molecule of water. Alkyne forms aldehydes or ketones as a product in this reaction. Aldehydes on oxidation will form carboxylic acids.
Complete Step by Step Solution:
Alkynes are unsaturated hydrocarbons having the general formula \[{{\rm{C}}_{\rm{n}}}{{\rm{H}}_{{\rm{2n - 2}}}}\].
Such compounds are more unsaturated than alkenes as they contain a triple bond in a molecule.
\[{{\rm{C}}_{\rm{2}}}{{\rm{H}}_{\rm{2}}}\] or acetylene is the first member of this series with two carbon atoms joined by one triple bond.
The IUPAC name of acetylene is ethyne.
Ethyne when treated with hot dilute sulfuric acid and mercury (I) hydroxide undergoes hydration.
A molecule of water gets added to it.
Vinyl alcohol is formed as the resulting product.
Vinyl alcohol being unstable undergoes tautomerization to form acetaldehyde or ethanal.
So, A in the given reaction is acetaldehyde.
Oxidation is the reaction by which the addition of oxygen to a molecule happens.
Acetaldehyde on oxidation leads to the formation of acetic acid or ethanoic acid.
So, B is acetic acid.
The reaction happens as follows:

Image: hydration of acetylene followed by hydrolysis
So, option A is correct.
Additional Information: Compounds whose structure differs in the arrangement of atoms but exists simultaneously in dynamic equilibrium with each other are called tautomers. This phenomenon is called tautomerism.
Note: Acetylene in the reaction with HgOH and dilute sulfuric acid leads to the formation of vinyl alcohol. Vinyl alcohol tautomerizes to form acetaldehyde. Acetaldehyde on oxidation forms acetic acid.
Complete Step by Step Solution:
Alkynes are unsaturated hydrocarbons having the general formula \[{{\rm{C}}_{\rm{n}}}{{\rm{H}}_{{\rm{2n - 2}}}}\].
Such compounds are more unsaturated than alkenes as they contain a triple bond in a molecule.
\[{{\rm{C}}_{\rm{2}}}{{\rm{H}}_{\rm{2}}}\] or acetylene is the first member of this series with two carbon atoms joined by one triple bond.
The IUPAC name of acetylene is ethyne.
Ethyne when treated with hot dilute sulfuric acid and mercury (I) hydroxide undergoes hydration.
A molecule of water gets added to it.
Vinyl alcohol is formed as the resulting product.
Vinyl alcohol being unstable undergoes tautomerization to form acetaldehyde or ethanal.
So, A in the given reaction is acetaldehyde.
Oxidation is the reaction by which the addition of oxygen to a molecule happens.
Acetaldehyde on oxidation leads to the formation of acetic acid or ethanoic acid.
So, B is acetic acid.
The reaction happens as follows:

Image: hydration of acetylene followed by hydrolysis
So, option A is correct.
Additional Information: Compounds whose structure differs in the arrangement of atoms but exists simultaneously in dynamic equilibrium with each other are called tautomers. This phenomenon is called tautomerism.
Note: Acetylene in the reaction with HgOH and dilute sulfuric acid leads to the formation of vinyl alcohol. Vinyl alcohol tautomerizes to form acetaldehyde. Acetaldehyde on oxidation forms acetic acid.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

JEE Atomic Structure and Chemical Bonding important Concepts and Tips

JEE Amino Acids and Peptides Important Concepts and Tips for Exam Preparation

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

Chemical Properties of Hydrogen - Important Concepts for JEE Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

Atomic Structure - Electrons, Protons, Neutrons and Atomic Models

Displacement-Time Graph and Velocity-Time Graph for JEE

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Learn About Angle Of Deviation In Prism: JEE Main Physics 2025

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

NCERT Solutions for Class 12 Chemistry Chapter 1 Solutions

Solutions Class 12 Notes: CBSE Chemistry Chapter 1

NCERT Solutions for Class 12 Chemistry Chapter 6 Haloalkanes and Haloarenes

NCERT Solutions for Class 12 Chemistry Chapter 2 Electrochemistry

Electrochemistry Class 12 Notes: CBSE Chemistry Chapter 2
