Find the quantity of dihydrogen required to prepare $2 \ L$ ammonia gas from $1 \ L$ dinitrogen.

Equal volumes of $0.1 \ M$ $AgNO_3$ and $0.2 \ M$ $NaCl$ are mixed. The concentration of $NO_3^-$ ion in the mixture will be ............ $M$.

At $300 \ K$ and $1 \ \text{atm}$ pressure,$10 \ mL$ of a hydrocarbon required $55 \ mL$ of $O_2$ for complete combustion,and $40 \ mL$ of $CO_2$ is formed. The formula of the hydrocarbon is

$A$ $40 \%$ $HCl$ solution has density $1.2 \ g \ mL^{-1}$. The molarity of the solution is nearly . . . . . . (in $M$)

$10 \ mL$ of a gaseous hydrocarbon on combustion gives $40 \ mL$ of $CO_{2(g)}$ and $50 \ mL$ of $H_2O_{(g)}$. The hydrocarbon is $-$

The number of molecules of $CO_2$ liberated by the complete combustion of $0.1 \ mol$ of graphite in air is