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प्रश्न
What is the action of following on phenol at low temperature?
- dil. HNO3
- conc. H2SO4
- Br2/CS2
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उत्तर
- Dilute HNO3: Phenol reacts with dilute nitric acid at low temperature to give a mixture of ortho- and para-nitrophenol.
- Conc. H2SO4: At room temperature (298 K), phenol reacts with concentrated sulphuric acid to form o-phenolsulphonic acid.
- Br2 in CS2: When a reaction is carried out in a solvent of lower polarity like CS2 a mixture of ortho- and para-bromophenol is formed.
संबंधित प्रश्न
Answer in brief.
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Reaction between hot conc. HI and anisole gives ______________
Write the reactions for the preparation of carbolic acid from aniline.
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Phenol reacts with concentrated nitric acid in the presence of cone. H2SO4 to form ____________.
In the Lucas test for alcohols, the appearance of turbidity is due to the formation of ____________.
Which of the following reagents are required in the conversion of phenol to salicylic acid?
Phenol is obtained from cumene ____________.
Sodium metal with ethyl alcohol gives __________ gas.
The CORRECT decreasing order of boiling points for isomeric primary (1°), secondary (2°) and tertiary (3°) alcohols is ____________.
Carbolic acid is oxidised by acidified sodium dichromate to give ______.
In Dow process, chlorobenzene is converted into phenol by ____________.
+I effect of alkyl groups in alcohols increases the stability of ____________.
Phenoxide ion is more stable than phenol due to the ____________.
The most resistant alcohol towards oxidation reaction is:
Identify reagents X, Y and Z.
Which of the following alcohols has tertiary allylic carbon?
Which of the following reagents is used to convert phenol to benzene?
Which following reagent is used to obtain alkene from alcohol?
Identify 'Z' in the following series of reaction:
\[\ce{Butan - 2 - ol ->[PCl3] X ->[alco. KOH] Y ->[i) H2SO4][ii) H-OH/heat] Z}\]
Name the catalyst used in commercial method of preparation of phenol.
What is the product formed when aniline is treated with \[\ce{NaNO2 + HCl}\] previous to hydrolysis?
Write the product when 1°, 2° and 3° alcohol vapours are passed over hot copper.
