Carbonyl Compounds - exam practice

Which carbonyl compound reacts with iodine in the presence of alkali to form a yellow solid?

Propanone has a much higher boiling temperature than butane.

The main reason for this is

Ethanal may be prepared by

CH₃CH₂COCH₂CH₃ reacts with hydrogen cyanide to form an organic product called a hydroxynitrile.

Which feature applies to the hydroxynitrile product?

Which reagent will give similar results with both butanone and butanal?

3-methylbutanone is treated with alkaline aqueous iodine. The mixture of products is then acidified.

Which compound is present in the final mixture of products?

Ketones react with hydrogen cyanide, HCN, in the presence of cyanide ions, CN^-.

Which of these ketones does not form a racemic mixture in this reaction?

Ketones react with hydrogen cyanide, HCN, in the presence of cyanide ions, CN^-.

This type of reaction is classified as

Name the functional group in HCHO.

Which of the following compounds would form an orange-red precipitate when heated with Fehling’s solution?

Which alcohol could not be produced by the reduction of an aldehyde or a ketone?

Which compound forms optically active compounds on reduction?

What is the functional group in C₆H₅COCH₃?

Compound X contains two functional groups.

Which reagent will react with only one of the functional groups?

Structural isomerism and stereoisomerism should be considered when answering this question.

Each of the following carbonyl compounds is reacted with LiAlH₄. The product of each reaction is heated with concentrated phosphoric acid at 170°C, generating one product or a mixture of isomers.

Which carbonyl compound will produce the most isomers?

What is the formula of the pale yellow solid formed when propanone reacts with iodine in the presence of sodium hydroxide?

Which compound reacts with 2,4-dinitrophenylhydrazine reagent but does not react with Tollens’ reagent?

Compound X, CH₃CH(OH)CH(CHO)CH₃, is heated under reflux with an excess of acidified K₂Cr₂O₇ to form compound Y.

Both X and Y are separately warmed with Fehling’s solution and the observations noted.

What are the observations?

Alcohol Y gives product Z after mild oxidation. Z gives a positive result with Tollens’ reagent and with 2,4-dinitrophenylhydrazine reagent.

What could be the identity of alcohol Y?

Which reagent cannot be used to distinguish between ethanal and propanone?

A compound, Q, gives an orange precipitate with 2,4-dinitrophenylhydrazine.

Compound Q is resistant to oxidation.

On reduction, Q gives a product made up of a pair of optical isomers.

Which of the following compounds could be compound Q?

Which of these compounds reacts with iodine and sodium hydroxide in solution to produce a pale yellow precipitate?