The volume (in $mL$) of $0.1\, N$ $NaOH$ required to neutralize $10\, mL$ of $0.1\, N$ phosphinic acid is........

The normality of $2 \ M$ sulphuric acid is: (in $N$)

$100 \, mL$ of $Na_{3}PO_{4}$ solution contains $3.45 \, g$ of sodium. The molarity of the solution is $..... \times 10^{-2} \, mol \, L^{-1}$ $(Nearest \, integer)$.
[$Atomic \, Masses - Na: 23.0 \, u, O: 16.0 \, u, P: 31.0 \, u$]

If the density of $1 \ mol$ of a gas at $NTP$ is $0.1784 \ g/L$,what is the weight of $1 \ mol$ of the gas in $g$?

An ideal gas mixture of $C_2H_6$ and $C_2H_4$ occupies a volume of $28 \ L$ at $1 \ atm$ and $273 \ K$. This mixture reacts completely with $128 \ g$ of $O_2$ to produce $CO_2$ and $H_2O_{(l)}$. What is the mole fraction of $C_2H_4$ in the mixture?

$20 \ mL$ of $0.2 \ M \ Al_2(SO_4)_3$ is mixed with $20 \ mL$ of $6.6 \ M \ BaCl_2$. The concentration of $Cl^{-}$ ion in the final solution is $......... \ M$.