$15 \ mL$ of $0.2 \ N$ alkali is required to complete neutralization of $30 \ mL$ acid solution. The concentration of the acid solution is ..... $N$.

The weight of $1 \ L$ of a hydrocarbon is more than that of $1 \ L$ of $CO_2$ at the same temperature and pressure. What is the molecular formula of the hydrocarbon?

$A$ pre-weighed vessel was filled with oxygen at $N.T.P.$ and weighed. It was then evacuated,filled with $SO_2$ at the same temperature and pressure,and again weighed. The weight of oxygen will be

$A$ $240 \ mL$ mixture of $CO_2$ and $CO$ is passed over red-hot coke. The $CO_2$ is completely reduced to $CO$. When the resulting gas is brought to the same temperature and pressure,the volume becomes $300 \ mL$. What is the volume of $CO$ in the original mixture in $mL$?

$29.2 \% (w/w)$ $HCl$ stock solution has a density of $1.25 \ g \ mL^{-1}$. The molecular weight of $HCl$ is $36.5 \ g \ mol^{-1}$. The volume $(mL)$ of stock solution required to prepare a $200 \ mL$ solution of $0.4 \ M$ $HCl$ is :

The normality of $0.3 \ M$ phosphorous acid $(H_3PO_3)$ is