Question

The number of moles of $CuO$, that will be utilized in Dumas method for estimation nitrogen in a sample of $57.5g$ of $N,N$-dimethylaminopentane is ___ $\times 10^{-2}.($ Nearest integer $)$

Answer 1

Answer: 1125

Moles of $N$ in $N,N$ - dimethylaminopentane
$=\left(\frac{57.5}{115}\right)=0.5$ mol
$\Rightarrow C_7{H}_{17}N+\frac{45}{2}CuO\to 7C{O}_2+\frac{17}{2}{H}_{2}O+\frac{1}{2}{N}_2+\frac{45}{2}Cu$
$\frac{n_{CuO}\text{ reacted }}{\left(\frac{45}{2}\right)}=\frac{n_{C_7{H}_{17}N}\text{ reacted }}{1}$
$\Rightarrow n_{CuO}$ reacted $=\left(\frac{45}{2}\right)\times 0.5=11.25$