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CBSE Class 12 Chemistry 2019 Outside Delhi Set 2 Solved Paper

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Question : 25 of 27
Marks: +1, -0
SECTION - D
(a) Give equations of the following reactions:
(i) Phenol is treated with conc. HNO3\mathrm{HNO}_3.
(ii) Propene is treated with B2H6\mathrm{B}_2\mathrm{H}_6 followed by H2O2/OH−\mathrm{H}_2\mathrm{O}_2 / \mathrm{OH}^{-}.
(iii) Sodium t-butoxide is treated with CH3Cl\mathrm{CH}_3\mathrm{Cl}.
(b) How will you distinguish between butan-1-ol and butan-2-ol?
(c) Arrange the following in increasing order of acidity: Phenol, Ethanol, Water
OR
(a) How can you obtain Phenol from (i) Cumene, (ii) Benzene sulphonic acid, (iii) Benzene diazonium chloride?
(b) Write the structure of the major product obtained from dinitration of 3-methylphenol.
(c) Write the reaction involved in Kolbe's reaction.
Solution:  
(a) (i)
(ii)
(iii)
Na+O−−CCH3CH3−CH3+CH3Cl→CH3O−CCH3CH3−CH3+NaCl\mathrm{Na}^{+}\mathrm{O}^{-} - \overset{\mathrm{CH}_3}{\underset{\mathrm{CH}_3}{\mathrm{C}}} - \mathrm{CH}_3 + \mathrm{CH}_3\mathrm{Cl} \rightarrow \mathrm{CH}_3\mathrm{O} - \overset{\mathrm{CH}_3}{\underset{\mathrm{CH}_3}{\mathrm{C}}} - \mathrm{CH}_3 + \mathrm{NaCl}
Sodium t-butoxide       \;\;\; Chloromethane       \;\;\; 2-Methoxy 2-Methyl propane
(b) Iodoform test: Butan −2−ol-2-\mathrm{ol} (secondary alcohol) reacts with iodine and NaOH\mathrm{NaOH} to give yellow precipitate of CHI3\mathrm{CHI}_3 (iodoform) whereas butan -1 -ol does not react with iodine and NaOH\mathrm{NaOH}.
CH3CH2CH∣OHCH3+4I2+6NaOH→\mathrm{CH}_3\mathrm{CH}_2\overset{\mathrm{OH}}{\overset{\vert}{\mathrm{CH}}}\mathrm{CH}_3 + 4\mathrm{I}_2 + 6\mathrm{NaOH} \rightarrow C2H5COONa+CHI3+5NaI+5H2OChloroform\underset{\text{Chloroform}}{\mathrm{C}_2\mathrm{H}_5\mathrm{COONa} + \mathrm{CHI}_3 + 5\mathrm{NaI} + 5\mathrm{H}_2\mathrm{O}}
OH−CH2−CH2−CH2−CH3\mathrm{OH}-\mathrm{CH}_2-\mathrm{CH}_2-\mathrm{CH}_2-\mathrm{CH}_3 +I2+NaOH→+ \mathrm{I}_2 + \mathrm{NaOH} \rightarrow No reaction
OR
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