Chemistry

11.53 

1. When N –propyl methyl ether reacts with HBr, it forms propanol and bromomethane, n- propyl methyl ether will cleave at O . and H⁺ will attack at O, and Br^- will attack CH ⁺

2. When Ethoxybenzene Reacts with HBr, it forms Phenol and bromoethane, Ethoxybenzene cleaves at H⁺ will attack at O, and Br^- will attack C H ⁺

3. When nitrating mixture reacts with ethoxy benzene introduction of nitro group is occurred at para position as it will give the stable product without

4. As HI is a strong nucleophile it will protonate the oxygen, to form a good leaving And I^- will attack at C (CH₃)₃⁺ to give tert- butyl iodide and ethanol.

4.34. The combining atomic orbitals should have comparable energies like, 1s orbital of one atom can combine with 1s atomic orbital of another atom, 2s can combine with 2s.

The combining atomic orbitals must have proper orientations so that they are able to overlap to a considerable extent.

The extent of overlapping should be large.

11.52

Set (ii) is appropriate Because CH₃Br is only a nucleophile whereas CH₃ONa is nucleophile as well as strong base, so the elimination reaction can occur,

11.51

During Williamson synthesis of ethers, an alkyl halide reacts with an alkoxide (ion with –ve charge on the oxygen of alcohol and + ve charge on alkali metal like Na) ion. it is an S_N2 reaction. In the reaction, alkyl halides should be least hindered. Hence, an alkyl halide is obtained from ethanol and alkoxide ion from 3-methylpentan-2-ol. The reactions are shown below:

11.50 

1. Phenol on mixing with chloroform and NaOH at 340K followed by Acidic hydrolysis, salicyl aldehyde is formed. When carbon tetrachloride (CCl₄) is used at the place of chloroform salicylic acid is This type of reaction is known as Reimer - Tiemann reaction.

2. The sodium phenoxide reacts with CO₂ under pressure 4-7 atm at a 400K temperature to form sodium salicylate, which on acidification yields salicylic acid. This type of reaction is known as Kolbe's

11.49.

Resonating structures of o-nitrophenoxide ions that are formed by the loss of a proton from o-nitrophenol are as follows:

Resonating structures of p-nitrophenoxide ions that are formed by the loss of a proton from p- nitrophenol are as follows:

Resonating structures of phenoxide ions that are formed by the loss of a proton from phenol are as follows:

It is clearly evident from the above structures that due to —R-effect of— NO₂NO₂ group, o-and p-nitrophenoxide ions are more stable than phenoxide ions. Consequently, o- and p- nitrophenols are more acidic than phenols.

11.47

(a) (i) Primary alcohols do no react appreciably with Lucas' reagent (HCl –ZnCl₂) at room temperature.

      (ii) Tertiary alcohol reacts immediately with Lucas 'reagent.