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Q1. What is Rosenmund reaction?

Solution

Acyl chloride (acid chloride) is hydrogenated over catalyst, palladium on barium sulphate. This reaction is called Rosenmund reduction. Benzoyl chloride                                                Benzaldehyde

Q2. What is Esterification reaction? Write the mechanism.

Solution

Q3. How will you convert propanoic acid to butanoic acid?

Solution

Q4. What happens when benzene is treated with acetyl chloride?

Solution

    Benzene                                                  Acetophenone

Q5. What happens when propanoic acid is treated with LiAlH₄ and the product is treated with conc. H₂SO₄ at 433K?

Solution

Propanoic acid when treated with LiAlH₄ forms propan-1-ol which on treatment with conc. H₂SO₄ at 433K forms propene.

Q6. Write a note on Hell-Volhard-Zelinsky Reaction.

Solution

In Hell-Volhard-Zelinsky Reaction, Carboxylic acids having an α- hydrogen are halogenated at the α- position on treatment with chlorine or bromine in the presence of  red phosphorous to give α-halo carboxylic acids.

Q7. Compound A C₅H₁₀O forms a Phenylhydrazone and gives negative Tollens and Iodoform tests. Compound A on reduction gives n-Pentane and on oxidation gives Propionic acid and Formic acid. Give the structure of the compound A and explain the reactions.

Solution

Q8. How to obtain Salicylaldehyde from Phenol?

Solution

Reimer-Tiemann reaction is a method for the preparation Ortho-hydroxybenzaldehyde. In this method Phenol is treated with Chloroform and Alkali at 333-343K when o-hydroxybenzaldehyde is obtained. Phenol                                                                                            Salicyaldehyde

Q9. What happens when Acetic acid is heated with Ethyl alcohol in presence of conc. H₂SO₄?

Solution

When acetic acid is heated with ethyl alcohol in presence of conc. H₂SO₄ , ethyl acetate is obtained.  

Q10. Write a note on aldol condensation?

Solution

Aldehyde and ketone having α-H atom are treated with a dilute alkali, two molecules of such compound condense to form β-hydroxy aldehyde and a β-hydroxy ketone. This reaction is called as Aldol condensation.