If the mixture of $7 \ g$ of $N_2$ and $8 \ g$ of $Ar$ in a cylinder has a total pressure of $27 \ bar$,what is the partial pressure of $N_2$ (in $bar$)? (Atomic mass of $N = 14 \ g \ mol^{-1}$,$Ar = 40 \ g \ mol^{-1}$)

$12 \ g$ of $Mg$ (atomic mass $24$) will react completely with acid to give:

$28 \ g$ $KOH$ is required to completely neutralize $CO_2$ produced on heating $60 \ g$ of impure $CaCO_3$. The percentage purity of $CaCO_3$ is approximately (molar masses of $KOH$ and $CaCO_3$ are $56$ and $100 \ g \ mol^{-1}$, respectively).

The volume of $0.1 \ M$ oxalic acid that can be completely oxidized by $20 \ mL$ of $0.025 \ M$ $KMnO_4$ solution is (in $mL$)

What is the normality of $1.5 \ M \ H_3PO_4$ (in $.5$)?

$16.8 \ L$ of a gas mixture containing $H_2$ and $O_2$ is formed at $NTP$ by the electrolysis of water. What is the mass of the electrolysed water in $g$?