\[\begin{array}{cc}\ce{\underset{\text{Ethylamine}}{CH3 – CH2 – NH2} + HNO2 ->[i. NaNO2/HCl,273 K][ii. H3O+]\underset{\text{Ethanol}}{CH3 – CH2 – OH} + N2↑H2O}\\
\ce{CH3 – CH2 – OH + [O]->[K2Cr2O7][dil.H2SO4,Δ]\underset{\text{Acetic acid}}{CH3 – COOH} + H2O}\\
\ce{\underset{\text{Acetic acid}}{CH3 – COOH} + NH3 ⇌ \underset{\text{Ammanium carboxylate}}{CH3 – COO^-NH^+4} ->[\Delta][-H2O]\underset{\text{Acetamide}}{CH3 – CONH2}}\\
\ce{O}\phantom{…………………………………………………….}\\
||\phantom{…………………………………………………….}\\
\ce{\underset{\text{Acetamide}}{CH3 – C – NH2} + Br2 + 4KOH_{(aq)}->[\Delta]\underset{\text{Methylamine}}{CH3 – NH2} + 2KBr + K2CO3 + 2H2O
\phantom{}}
\end{array}\]