Which reagent is used to distinguish between C$_2$H$_5$NH$_2$ and (C$_2$H$_5$)$_2$NH ?
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- KMnO$_4$
- CHCl$_3$ + KOH (ethanolic)
- NaOH + I$_2$
- Neutral FeCl$_3$
The Correct Option is B
Solution and Explanation
Step 1: Carbylamine reaction. Primary amines react with: \[ CHCl_3 + KOH \] to produce foul-smelling isocyanides. General reaction: \[ RNH_2+CHCl_3+3KOH \rightarrow RNC+3KCl+3H_2O \]
Step 2: Behaviour of ethylamine. \[ C_2H_5NH_2 \] is a primary amine. Therefore it gives positive carbylamine test.
Step 3: Behaviour of diethylamine. \[ (C_2H_5)_2NH \] is a secondary amine. Secondary amines do not give carbylamine test.
Step 4: Conclusion. Only ethylamine produces foul-smelling isocyanide. Therefore the reagent used for distinction is: \[ \boxed{CHCl_3 + KOH} \] Hence option (B) is correct.
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(ii) In increasing order of basic strength: C6H5NH2 , C6H5N(CH3 )2 , (C2H5 )2NH and CH3NH2
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How will you convert:
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(ii) Hexanenitrile into 1-aminopentane
(iii) Methanol to ethanoic acid
(iv) Ethanamine into methanamine
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(viii) Propanoic acid into ethanoic acid?
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