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How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Reactions Due to α-hydrogen
Complete the synthesis by giving missing starting material, reagent or product.
Concept: Preparation of Aldehydes and Ketones
Write the product(s) in the following reactions
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Other Reactions
Write the equations involved in the following reactions :
Wolff-Kishner reduction
Concept: Acids >> Nomenclature of Carboxylic Acids
Account for the following:
Carboxylic acid is a stronger acid than phenol.
Concept: Acids >> Chemical Reactions of Carboxylic Acids - Reactions Involving Cleavege of O-H Bond
Write the chemical equations to illustrate the following name reactions:
Aldol condensation
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Other Reactions
Give the IUPAC name of the following compound.
CH3 − CH = CH − CHO
Concept: Aldehydes and Ketones >> Nomenclature of Aldehydes and Ketones
Complete the following:
\[\ce{CH3CN ->[1. AlH(i - Bu)2][2. H2O] 'A' ->[H2N-OH][H^+] 'B'}\]
Concept: Aldehydes and Ketones >> Nomenclature of Aldehydes and Ketones
Write IUPAC name of the following compound:
Concept: Aldehydes and Ketones >> Nomenclature of Aldehydes and Ketones
Convert the following:
Propan-1-ol to 2-Bromopropanoic acid
Concept: Acids >> Chemical Reactions of Carboxylic Acids - Substitution Reactions in the Hydrocarbon Part
Convert the following:
Acetaldehyde to But-2-enal
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Reactions Due to α-hydrogen
What happens when ethanal is treated with excess ethanol and acid?
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Nucleophilic Addition Reactions
Write the main product in the following reaction:
\[\ce{CH3CH2CHO ->[Zn(Hg)/Conc. HCl]}\]
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Reduction
Write the main product in the following reaction:
Concept: Uses of Carboxylic Acids
Which will undergo faster nucleophilic addition reaction?
Acetaldehyde or Propanone
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Nucleophilic Addition Reactions
What is the composition of Fehling's reagent?
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Oxidation
Which of the following is most reactive in nucleophilic addition reactions?
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Nucleophilic Addition Reactions
The following questions are case-based questions. Read the passage carefully and answer the questions that follow:
| The carbon-oxygen double bond is polarised in aldehydes and ketones due to higher electronegativity of oxygen relative to carbon. Therefore, they undergo nucleophilic addition reactions with a number of nucleophiles such as HCN, NaHSO3, alcohols, ammonia derivatives and Grignard reagents. Aldehydes are easily oxidised by mild oxidising agents as compared to ketones. The carbonyl group of carboxylic acid does not give reactions of aldehydes and ketones. Carboxylic acids are considerably more acidic than alcohols and most of simple phenols. |
Answer the following:
(a) Write the name of the product when an aldehyde reacts with excess alcohol in the presence of dry HCl. (1)
(b) Why carboxylic acid is a stronger acid than phenol? (1)
(c) (i) Arrange the following compounds in increasing order of their reactivity towards CH3MgBr: (1)
CH3CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
\phantom{....}\ce{O}
\end{array}\], \[\begin{array}{cc}
\ce{CH3-C-CH3}\\
||\\
\ce{O}
\end{array}\]
(ii) Write a chemical test to distinguish between propanal and propanone. (1)
OR
(c) Write the main product in the following: (2)
| (i) |  |
| (ii) |  |
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Nucleophilic Addition Reactions
Why is the boiling point of aldehydes and ketones lower than that of corresponding carboxylic acids?
Concept: Physical Properties of Aldehydes and Ketones
An organic compound 'A' with molecular formula C5H8O2 is reduced to n-pentane with hydrazine followed by heating with NaOH and glycol. 'A' forms a dioxime with hydroxylamine and gives a positive iodoform and Tollen's test. Identify 'A' and give its reaction for iodoform and Tollen's test.
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Oxidation
