$0.1840\, gm$ of organic compound gave $30 \,mL$ of nitrogen which is collected at $287\, K$ And $758\,mm$ of $Hg$.
Given ; Aqueous tension at $287 \,K =14 \,mm$ of $Hg$. Hence actual pressure $=(758-14)$
$=744\, mm \text { of } Hg \text { . }$
Volume of nitrogen at $STP =\frac{273 \times 744 \times 30}{287 \times 760}$
$V =27.935 \,mL$
$\because 22400 mL$ of $N _{2}$ at STP weighs $=28\, gm .$
$\therefore 27.94 mL$ of $N _{2}$ at STP weighs $=$
$\left(\frac{28}{22400} \times 27.94\right)\, gm$
$=0.0349 \,gm$
Hence $=\left(\frac{0.0349}{0.1840} \times 100\right)$
$=18.97\, \%$
Rond off. Answer $=19 \,\%$