Na+ and Cl– ions attract H2O molecules more strongly than ether molecules, thus the solubility of ether decreases in saturated solution of NaCl. When 3-methylbutan-2-ol is treated with HBr, the following reaction takes place: Answer:
(c) CH3—CHO How are the following conversions carried out: In case dehydration of the given alcohol gives two alkenes, then see which alkene will give the desired alcohol. The fermentation reaction starts and the enzyme Invertase (From Yeast) converts sucrose into glucose and fructose which are then converted into ethanol by Zymase (From Yeast). Answer: Question 32. (ii) Nitration of anisole : Anisole reacts a mixture of concentrated sulphuric and nitric acids to yield a mixture of ortho and para nitroanisole. (403K) and 4-7 atm pressure, sodium salicylate is formed. (i) When ethyl alcohol is heated in excess of cone. 0000012242 00000 n Answer: -R effect results in +ve charge on O-atom and hence facilitates the release of proton. It is an example of electrophilic aromatic substitution reaction.

Answer: (iii) Williamson-1 ether synthesis : This is the best method for preparation of ethers because both symmetrical and unsymmetrical (Aliphatic as well as aromatic) ethers can be prepared. HCl Answer: If a blood red colour is obtained, the original alcohol is primary. The method according to claim 7 wherein the reaction zone of the reactor is maintained at a pressure of from 10mm to 200mm mercury. (x) Ethoxybenzene (iii) Ethyl acetate from Ethanol: It is an example of nucleophilic substitution reaction in which halide ion (X-–) of haloalkane is replaced by alkoxy or aroxy group. Question 4. (a) Diethyl ether MP Board Textbook Solutions for Class 6 to 12. Draw the resonance structures of the corresponding phenoxide ions. (a) Methyl alcohol, Question 17. (iii) Ethyl acetate from ethanol But another molecule of alcohol cannot attack it due to steric hindrance. The reactions showing acidic character of phenols are : This is the old method and is used at present also.

Recovery of methyl alcohol from pyroligneous acid : Pyroligneous acid contains methyl alcohol (2-4%), acetone (0-5 to 1%), acetic acid (about 10%) and water. Answer: Question 4. (a) Chlorobenzene

0000029472 00000 n

(b) CH3-OH At this time the Br2 addition rate is decreased to maintain a column temp of less than 100C (10 max. Background of Invention This invention relates to bromination of aromatic compounds and more particularly relates to bromination of anisole compounds particularly alkylated anisoles. 0000060303 00000 n 82 0 obj << /Linearized 1 /O 85 /H [ 1232 397 ] /L 332285 /E 103509 /N 5 /T 330527 >> endobj xref 82 35 0000000016 00000 n (b) CH3CHO (ii) The iodide is treated with silver nitrite to form nitroalkane.

In case of pent-2-one, both the carbon atoms of double bond have one H-atom. Step 3 : Elimination of a proton to form ethene: (d) CH3-O-CH3 Benzene is mixed in absolute spirit and fractionally distilled. Question 15. Question 11.33. Write Victor Meyer method to distinguish primary, secondary and tertiary alcohol. (iv) Friedel-Craft’s acetylation of anisole : Question 32. 0000001992 00000 n Answer: (i) Propene → Propan-2-ol.

0000005774 00000 n On boiling aqueous solution of this salt phenol is formed.

You can specify conditions of storing and accessing cookies in your browser. Anisole undergo bromination with bromine in ethanoic acid (acetic acid) to form mixture of ortho and para bromo anisole. Therefore, nucleophilic attack of CH3ONa followed by elimination of NaBr gives the desired ether. Methyl alcohol and acetone vapours pass over and are condensed. They will give the desired alcohol on adding a H2O molecule. (iv) Unsymmetrical ether : An unsymmetrical ether is an ether where two groups on the two sides of an oxygen atom differ (i.e., have and unequal number of carbon atoms. 6C6H5OH + FeCl3 → (C6H5O)6 Fe + 3HCl + 3H+. When yeast is mixed in glucose solution and kept at proper conditions, ethyl alcohol is formed as a result of fermentation. Isomers (ii), (vii) and (viii) contain chiral centres can exhibit enantiomerism. Write equation of the following reaction: Bromination of anisole in ethanoic acid medium. Thus, alkyl halide should be derivde from ethanol and alkoxide ion from 3-methyl pentan-2-ol. Answer. Explain the following with an example : The distillate contain 90% alcohol. Question 1.
What do you understand by Methylated spirit or denaturing alcohol ?

(iii) Aniline The complete reaction is as follows : Question 11. Give two reactions that show the acidic nature of phenol. Explain. As a result its boiling point is less than that of p-nitrophenol, which is not steam volatile and its molecules are linked by intermolecular H—bonding. How is ethyl alcohol obtained by molasses ? (i) 1°, (ii) 1°, (iii) 1°, (iv) 2°, (v) 2°, (vi) 3°. (ii) By alkaline fusion of sodium benzene sulphonate : On fusing sodium benzene sulphonate with NaOH, sodium phenoxide is formed which on acidification forms phenol. Solution : (i) (ii) (iii) (iv) Q11.32: Show how would you synthesise the following alcohols from appropriate alkenes? The boiling point of ethanol is higher than methoxymethane because of the presence of strong intermolecular hydrogen bonding between ethanol molecule. The vapor reactor heat tape is turned on and the voltage adjusted just high enough to prevent condensation of 3 methyl-anisole in the vapor reactor.The Br2 feed valve is opened and adjusted to give 0.2 mls ofvapor per minute.

It is of two types : It is used for the preparation of spirit, varnish etc. (ii) 5-Ethylheptane-2,4-diol (ii) Nitration of anisole. (a) LiAlH4 (iii) Dilute HNO3 with phenol. (b) Phenol

H2SO4 (i) 1-Ethoxy-2-methylpropane (iv) Hex-l-en-3-ol. 9. Question 14. Most acidic among the four compound is : Click here to get an answer to your question ️ Write equation of the following reaction: Bromination of anisole in ethanoic acid medium. Similarly, the 3° alcohol (CH3)3COH forms isobutane. Phenol gives white precipitate of 2, 4, 6-tribromo- phenol with bromine water. 8.

Question 16.

How can you change the following : (i) Methanol to ethanol, (ii) Ethanol to methanol. As a result, the incoming substituents are directed to the ortho and para positions in the benzene ring. This reaction will follow the criteria of, Anisole ---- in the presence of Br2 in Ethanoic acid -- p-Bromoanisole (major) + o-Bromoanisole (Minor). In set (B) nucleophilic attack of 4-nitrophenoxide ion on methylbromide gives the desired product.

Azeotropic mixture of 74% water, 18 5% alcohol and 74% ben¬zene is distilled on 64-8% alcohol. But phenol reacts with NaOH and exhibits its strong acidic nature. 0000005624 00000 n If no colour is produced, the alcohol is tertiary. On heating formaldehyde with ………………. Salicylic acid is the starting material for the manufacture of aspirin which is an important analgesic. Answer: Answer: Which is identified by Lucas reagent:

(ii) Aryl halides and vinyl halides cannot be used as substrate for the preparation of aromatic aliphatic ether because aryl halide and vinyl halides are less reactive towards nucleophilic substitution reaction. Write Equations of the Following Reactions: Bromination of Anisole in Ethanoic Acid Medium. Answer: Write a notes on fermentation. The pyroligneous acid is taken in a copper vessel and distilled. Write equations of the following reactions: (i) Friedel-Crafts reaction-alkylation of anisole. A part of sulphuric acid is reduced by alcohol into sulphur dioxide.

After the formation of ethene, it is removed to shift the equilibrium in a forward direction. (b) Phenol

The addition of diborane to alkene to form trialkyl boranes followed by their oxidation with alkaline hydrogen peroxide to form alcohol is called hydroboration-oxidation. Answer: (i) Oxidation of propan-l-ol with alkaline KMnO4 solution. Show how would you synthesize the following alcohols from appropriate alkenes ? Concentration : Solution should be dilute (Concentration 8-10%). Abromine source 3 stirred by magnetic mixer 9 is maintained in a water bath 10 and via control valve 4 gas is inlet ultimately to the top of reflux column 2. Why ether is less soluble in saturated solution of NaCl ? Question 24.

The two -ve charge repel each other and therefore destabilize the o-methoxyphenoxide ion. Save my name, email, and website in this browser for the next time I comment. Answer: These prior art processes are characterized as contaminated with considerable amounts of 2,4-dibromoanisole. 2.

(iv) Ethanol from Glucose : Question 9. acids etc. (i) Reimer-Tiemann reaction : When phenol is treated with chloroform in presence of aqueous sodium hydroxide at 60°C, o-Hydroxy benzaldehyde (Salicylaldehyde) and p-Hydroxy benzaldehyde are formed. Answer: Solution : The alcohols given above can be synthesized by applying Markovnikov’s rule of acid-catalyzed hydration of appropriate alkenes. (iii) 3,5-Dimethylhexane -1, 3, 5-triol Question 19. (b) Ethyl alcohol (ii) It can also be observed from the resonance structure that the electron density increases more at the ortho para positions than at the meta position. (d) (C2H5)2 O. (b) Phenol, Question 12.