Compound $Y$ must give iodoform test. Further since $Y$ is obtained by the oxidation of $X$ which must be an alcohol $(CH_3CH_2OH)$ and thus $Y$ is $CH_3CHO$
${CH}_{4}+{I}_{2} \underset{\text { Reversible }}{\stackrel{{hv}}{\longrightarrow}} {CH}_{3}-{I}+{HI}$