हिंदी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction. Reason: Aromatic aldehydes are almost as reactive as formaldehyde.

Advertisements
Advertisements

प्रश्न

Assertion: Aromatic aldehydes and formaldehyde undergo Cannizaro reaction.

Reason: Aromatic aldehydes are almost as reactive as formaldehyde.

विकल्प

  • Assertion and reason both are correct and reason is correct explanation of assertion.

  • Assertion and reason both are wrong statements.

  • Assertion is correct statement but reason is wrong statement.

  • Assertion is wrong statement but reason is correct statement.

  • Assertion and reason both are correct statements but reasson is not correct explanation of assertion.

MCQ
Advertisements

उत्तर

Assertion is correct statement but reason is wrong statement.

Explanation:

There is no alpha hydrogen atom in the Cannizaro process. Formaldehyde and aromatic aldehydes do not contain alpha hydrogen. It proceeds through the Cannizaro reaction. Formaldehyde is the most reactive of all aldehydes.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 12: Aldehydes, Ketones and Carboxylic Acids - Multiple Choice Questions (Type - I) [पृष्ठ १७६]

APPEARS IN

एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 12
अध्याय 12 Aldehydes, Ketones and Carboxylic Acids
Multiple Choice Questions (Type - I) | Q 45 | पृष्ठ १७६

संबंधित प्रश्न

How will you bring about the following conversion in not more than two steps?

Ethanol to 3-Hydroxybutanal


Give reasons  Acetylation of aniline reduces its activation effect.


 Why is alpha (α) hydrogen of carbonyl compounds acidic in nature?


Write chemical equations of the following reaction : 

Propanone is treated with dilute Ba (OH)2-.


What is substituted imine called?


Which product is formed when the compound  is treated with concentrated aqueous \[\ce{KOH}\] solution?


Compounds A and C in the following reaction are:

\[\ce{CH3CHO ->[(i) CH3MgBr][(ii) H2O] (A) ->[H2SO4, Δ] (B) ->[Hydroboration oxidation] (C)}\]


Which of the following conversions can be carried out by Clemmensen Reduction?

(i) Benzaldehyde into benzyl alcohol

(ii) Cyclohexanone into cyclohexane

(iii) Benzoyl chloride into benzaldehyde

(iv) Benzophenone into diphenyl methane


Assertion: The α-hydrogen atom in carbonyl compounds is less acidic.

Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.


Cross aldol condensation occurs between


Predict the reagent for carrying out the following transformations:

Ethanal to 3-hydroxy butanal


\[\ce{CH3-CH2-CHO ->[dil][alkali] Product}\]

The product in the above reaction is:


The major product of the following reaction is:


Why is the α-hydrogens of aldehydes and ketones are acidic in nature?


Identify A and B:


When acetaldehyde is treated with dilute NaOH, the following reaction is observed.

\[\begin{array}{cc}
\ce{2CH3 - CHO ->[dil.NaOH] CH3 - CH - CH2 - CHO}\\
\phantom{...............}|\\
\phantom{.................}\ce{OH}
\end{array}\]

  1. What are the functional groups in the product?
  2. Can another product be formed during the same reaction? (Deduce the answer by doing atomic audit of reactant and product).
  3. Is this an addition reaction or condensation reaction?

Write a note on the aldol condensation reaction of acetaldehyde.


What is aldol condensation? Explain it with suitable examples.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×