Class 12th Chemistry 2017 Set1 Outside Delhi Board Paper Solution
Give reasons for the following:
(a) Red phosphorus is less reactive than white phosphorus .
(b) Electron gain enthalpies of helogens are largely negative.
(c) N2O5 is more acidic than N2O3.
(a) Red phosphorus is less reactive then white phosphorus because it is more stable due to its polymeric structure.
(b) The Electron gain enthalpy of halogens is highly negative because it needs only one electron to achieve nearest noble gas configuration.
(c) N2O5 is more acidic because it form HNO3 with H2O and while N2O3 forms HNO2 with H2O.
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Give simple chemical tests to distinguish between the following pairs of compounds.
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(ii) Acetophenone and Benzophenone
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(iv) Benzoic acid and Ethyl benzoate
(v) Pentan-2-one and Pentan-3-one
(vi) Benzaldehyde and Acetophenone
(vii) Ethanal and Propanal
- Q:-
How the following conversions can be carried out?
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(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
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