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Question 1

Write structures of main compounds A and B in each of the following reactions:

1.

CH $_3$ CN $\xrightarrow[\text{(ii) }{H_3}{\text{O}}^{+}]{{\text{(i) }CH_3\text{MgBr}}}{\text{A}}\xrightarrow{{\text{Zn(Hg) / conc. HCl}}}{\text{B}}$

2.

$\text{C}_6\text{H}_5\text{COOH} \xrightarrow{\text{PCl}_5} \text{A} \xrightarrow{\frac{\text{H}_2}{\text{Pd} - \text{BaSO}_4}} \text{B}$

Question 2

1.

What happens when phenol reacts with Conc. HNO3? Write equation only.

2.

What happens when phenol reacts with CHCl3 in presence of aqueous NaOH followed by acidification? Write equation only.

3.

Why does the reaction of CH3ONa with (CH3)3C - Br give 2-methylpropene and not (CH3)3C - OCH3?

Question 3

Iodoform test is not given by

Question 4

1.

Write the chemical equations for the reaction involved in cannizzaro reaction.
Draw the structure of semicarbazone of ethanol.
Why p$ k_{\alpha}$ of F-CH₂ -COOH is lower than that Cl-CH₂-COOH?
Write the product in the following reaction
$ C{H_3} - CH = CH - C{H_2}CN\xrightarrow[{(ii)\,\,{H_2}O}]{{(i)\,\,DIBAL - H}}$
How can you distinguish between propanal and propanone?

Question 5

1.

Which type of aldehyde undergo Cannizzaro reaction?

Question 6

How are the following conversions carried out?

1.

Convert propene to propan-2-ol.

2.

Convert ethyl chloride to ethanal.

Question 7

1.

Give chemical tests to distinguish between propanal and propanone.

2.

Give chemical tests to distinguish between benzaldehyde and acetophenone.

3.

How would you obtain butanoic acid from butanol?

4.

How would you obtain benzoic acid from ethyl benzene?

Question 8

1.

An organic compound with molecular formula C₉H₁₀O forms 2,4-DNP derivative, reduces Tollen's reagent and undergoes Cannizzaro reaction. On vigorous oxidation, it gives 1, 2-benzene dicarboxylic acid. Identify the compound.
Give the chemical tests to distinguish between
1. propanol and propanone
2. benzaldehyde and acetophenone
Arrange the following compounds in an increasing order of their property as indicated:
Acetaldehyde, acetone, methyl tert-butyl ketone (reactivity towards HCN).

Question 9

1.

Why is the C - O bond length in phenols less than that in methanol?

2.

Arrange the following in order of increasing boiling point: Ethoxyethane, Butanal, Butanol, n-butane

3.

How can phenol be prepared from anisole? Give reaction.

Question 10

Aldehydes, ketones and carboxylic acids are some of the important classes of organic compounds containing carbonyl group. These are highly polar molecules due to higher electro-negativity of oxygen relative to carbon in the carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes. Aldehydes and ketones undergo nucleophilic addition reactions onto the carbonyl group but carboxylic acid does not undergo nucleophilic addition reaction. The alpha (α) - hydrogens of aldehydes and ketones are acidic. Therefore aldehydes and ketones having at least one α-hydrogen undergo Aldol condensation. Aldehydes are easily oxidised by mild oxidising agents such as Tollens' reagent and Fehling's reagent. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and by hydrolysis of nitriles. Aromatic carboxylic acids are prepared by side-chain oxidation of alkyl benzenes. Carboxylic acids are considerably more acidic than alcohols and most of simple phenols.

1.

Why carboxylic acid does not give nucleophilic addition reactions like aldehydes and ketones?

Aldehydes Ketones and Carboxylic Acids Questionbank