Advertisements
Advertisements
Question
How is carbolic acid prepared from chlorobenzene?
Advertisements
Solution
1. Dow’s process:
i. When chlorobenzene is heated with excess of aqueous sodium hydroxide (NaOH) at 613 K under a pressure of 300 atmosphere, sodium phenoxide is formed.

ii. Sodium phenoxide when hydrolysed using dilute hydrochloric acid (HCl), phenol is obtained.

OR
Phenol can also be obtained by passing CO2 (carbon dioxide) gas, through aqueous solution of sodium phenoxide.

2. Raschig process (Industrial method):
i. When chlorobenzene is treated with steam (H2O) at 698 K in the presence of Ca3(PO4)2 or SiO2 as a catalyst, phenol is obtained.

ii. The hydrolysis can also be carried out by using water in the presence of copper catalyst at 673 K and under pressure.
Notes
(Any one method)
APPEARS IN
RELATED QUESTIONS
Write the structures of A and B in the following reactions

Name the reagents used in the following reactions:

Show how the following compound can be converted to benzoic acid.
Acetophenone
Show how the following compound can be converted to benzoic acid.
Bromobenzene
Predict the products formed when cyclohexanecarbaldehyde reacts with the following reagent.
Tollens’ reagent
How will you prepare the given compound from benzene? You may use any inorganic reagent and any organic reagent having not more than one carbon atom.
m-Nitrobenzoic acid
How will you prepare the given compound from benzene? You may use any inorganic reagent and any organic reagent having not more than one carbon atom.
p-Nitrobenzoic acid
How will you prepare the given compound from benzene? You may use any inorganic reagent and any organic reagent having not more than one carbon atom.
Phenylacetic acid
Name the reagents used in the following reactions:

What is the action of following reagents on glucose?
1. Bromine water
2. Hydroxylamine
The reagent which does not react with both, acetone and benzaldehyde.
Which is the most suitable reagent for the following conversion?
\[\begin{array}{cc}
\phantom{....................}\ce{O}\phantom{.....................................}\ce{O}\phantom{.}\\
\phantom{....................}||\phantom{......................................}||\phantom{.}\\
\phantom{}\ce{CH3 - CH = CH - CH2 - C - CH3 -> CH3 - CH = CH - CH2 - C - OH}\phantom{.}
\end{array}\]
Through which of the following reactions number of carbon atoms can be increased in the chain?
(i) Grignard reaction
(ii) Cannizaro’s reaction
(iii) Aldol condensation
(iv) HVZ reaction
Match the reactions given in Column I with the suitable reagents given in Column II.
| Column I (Reactions) |
Column II (Reagents) |
| (i) Benzophenone Diphenylmethane | (a) \[\ce{LiAlH4}\] |
| (ii) Benzaldehyde 1-Phenylethanol | (b) \[\ce{DIBAL-H}\] |
| (iii) Cyclohexanone Cyclohexanol | (c) \[\ce{Zn(Hg)/Conc. HCl}\] |
| (iv) Phenyl benzoate Benzaldehyde | (d) \[\ce{CH3MgBr}\] |
Assertion: Aldehydes and ketones, both react with Tollen’s reagent to form silver mirror.
Reason: Both, aldehydes and ketones contain a carbonyl group.
Substitution of one alkyl group by replacing hydrogen of primary amines

Y is:
Alkaline hydrolysis of C4H8Cl2 gives a compound (A) which on heating with NaOH and I2 produces a yellow precipitate of CHI3. The compound (A) should be ______.
A compound 'X' with molecular formula C3H8O can be oxidised to a compound 'Y' with the molecular formula C3H6O2 'X' is most likely to be ______.
Fill in the blanks by choosing the appropriate words from those given in the brackets:
[stable, low, aldehyde, unstable, 6, 4, ethane, Clemmensen’s, 2, 3, carboxylic acid, high, propane, Rosenmund's]
The primary alcohols are easily oxidised first into ______ and then into ______.
