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How will you differentiate between? (i) Aceetaldehyde and acetone. (ii) Aldehydes and ketones with (i) Tollens's regent (ii) Fehling's solution (iii) Acetone and diethyl ether (iv) Formaldehyde and acetaldehyde. (v) Ethyl alcohol and acetone (vi) Formaldehyde and ethylalcohol (vii) Pentan-2-one and pentan-3-one (viii) Benzaldehyde and acetophenone (ix) Benzaldehyde and acetaldehyde ltbr (x) Benzaldehyde and introbenzene. |
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Answer» Solution :(i) Acetaldehyde respods to following tests while acetone does not give any of them (a) Acetaldehyde + Schiff's REAGENT solution `rarr`Pink colour. ltbr (b) Acetaldehyde + Tollens's reagent `rarr` Silver mirror. (c) Acetaldehyde + Fehiling 's solution `rarrr` Red precipiate. (d) Acetaldehyde + SODIUM hydroxide (conc.)`rarr` Brown RESINOUS mass (ii) Same test asin (i) (iii)Acetone forms yellow coloured iodoforms when heated with `I_(2)` and NaOH,i.e., it gives iodoform test. Diethyl ether not give thsi test (iv) Acetaldeyde from yellow PRECIPITATE of iodoform with an alkaline solution of iodine,i.e., give idoforms test. Formaldeyhde does not give this test (v) Ethyl alcohol gives pink colour with ceric ammoinim nitrate while acetone does not. Acetone gives pink colour with an alkaline solution of sodium nitropurusside while ethyl alcohol does not (vi) Formaldehyde responds to following test while ethyl alcohol does not give any of them (a) HCHO+ Schiff's `rarr` Pink colour (b) HCHO+ Tollen's reagent `rarr` silver mirror HCHO+ Fehling's solution `rarr` Red precipitate Ethyl alcohol give iodoforms test while HCHO does not (vii) Pentan-2-one having -`COCH_(3)` group fros a yellow precipitate of iodoforms with an alkaline solution of iondine,i.e., gives idoforms test while pentan-3-one (viii) (a) Benzaldehyde forms sliver mirror with an ammoniacal silver nitrate solution while acetophenone does not. (b) Acetophenone forms yellow precipite of iodoforms with an alkaline solution of `I_(2)` . Benzaldehyde does not react (ix) Acetaldehyde gives iodoforms test, benzaldehyde does not. (b) Acetaldehyde gives red precipitate with Fehlings's solution while benzaldehyde does not react. (x) (a) Benzaldehyde reduces. Tollens' reagent while nitrobenzene does not. (b) Benzaldehyde gives pink colour Schiff's reaent but nitrobenzene does not (c) Nitrobenzene on reduction gives aniline which exhibites dye test. Benzaldehyde does not give dye test. |
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