$1.\,\,CH_3-C \equiv C -CH_3$
$2.\,\,CH_3 - CH_2 - CH_2 - CH_3$
$3. \,\,CH_3 - CH_2C \equiv CH$
$4.\,\,CH_3 - CH = CH_2$
ઇથાઇન $\xrightarrow[\begin{smallmatrix}
(2)\,\,excess\,I-\,C{{H}_{2}}\,-\,{{(C{{H}_{2}})}_{2}}-\,C{{H}_{3}} \\
(3)\,\,{{H}^{\oplus }}
\end{smallmatrix}]{(1)\,\,excess\,NaN{{H}_{2}}}$

