Formaldehyde $($CH$,$O$)$ can be produced industrially by partial oxidation with air over a silver catalyst. Suppose about $2/3$ mol formaldehyde is produced per $1$ mol methanol reacted and that, in addition, some formic acid, H$,,$ CO$,$ and CO$,$ are produced. In order to ensure high utilization of the reactant, the product gas is scrubbed with HO to separate the off$-$gases. The residue Is distilled to produce a pure recycle methanol. Assuming that the reactor inlet gas to the reactor is $35\%($mol$)$ methanol, calculate the moles of formaldehyde produced per mole of feed methanol, given the off$-$ gas composition $20\mathrm{.}2\%$ H$2,4\mathrm{.}8\%$ CO$,,0\mathrm{.}2\%$ CO$,74\mathrm{.}5\%$ N$2,$ and $0\mathrm{.}3\%02$

Use Mass balances