In the above reaction,$3.9 \ g$ of benzene on nitration gives $4.92 \ g$ of nitrobenzene. The percentage yield of nitrobenzene in the above reaction is............. $\%$. (Round off to the Nearest Integer).
(Given atomic mass: $C : 12.0 \ u$,$H : 1.0 \ u$,$O : 16.0 \ u$,$N : 14.0 \ u$)

What volume of $2 \,M \,H_2SO_4$ is required to prepare $100 \,mL$ of $0.2 \,N \,H_2SO_4$ solution (in $\,mL$)?

$A$ $1.85 \ g$ sample of an arsenic containing pesticide was chemically converted to $AsO_4^{3-}$ (atomic mass of $As = 74.9$) and titrated with $Pb^{2+}$ to form $Pb_3(AsO_4)_2$. If $20 \ mL$ of $0.1 \ M \ Pb^{2+}$ is required to reach the equivalence point,the mass percentage of arsenic in the pesticide sample is closest to

In the balanced combustion reaction of $1 \, mol$ of $C_xH_{2n-2}$ hydrocarbon,the coefficients of $O_2$,$CO_2$,and $H_2O$ will be respectively ...

What is the number of hydrogen molecules needed to synthesize $3.4 \text{ g}$ of ammonia by reaction with nitrogen?

$40\%$ of a mixture of $0.2 \ mol$ of $N_2$ and $0.6 \ mol$ of $H_2$ reacts to give $NH_3$ according to the equation:
$N_{2(g)} + 3H_{2(g)} \rightleftharpoons 2NH_{3(g)}$
at constant temperature and pressure. What is the ratio of the final volume to the initial volume of gases?