Calculate the amount of hydrogen gas required to produce $100 \text{ g}$ of ammonia by the reaction of $N_{2(g)}$ and $H_{2(g)}$ gases. (in $\text{ g}$)

Molarity of a solution containing $1 \ g$ $NaOH$ in $250 \ mL$ of solution is ...... $M$.

The volume in $mL$ of $0.1 \ M$ solution of $NaOH$ required to completely neutralize $100 \ mL$ of $0.3 \ M$ solution of $H_3PO_3$ is

$A$ pre-weighed vessel is filled with $O_2$ and weighed at $STP$. It is then evacuated and filled with $SO_2$ gas at the same temperature and pressure,and weighed again. The weight of $O_2$ will be:

$A$ sample of nitric acid has a density of $1.41 \ g \ mL^{-1}$ and the mass percentage of nitric acid is $69 \%$. Calculate the concentration of nitric acid in the sample in moles per liter. (in $M$)

$Elodea$ is an aquatic plant that performs photosynthesis in water. The photosynthesis reaction is given by: $6CO_{2(g)} + 6H_2O_{(l)} \to C_6H_{12}O_{6(aq)} + 6O_{2(g)}$. Calculate the mass of $CO_2$ in $g$ required to produce $112 \, mL$ of oxygen at $STP$.