The molarity of $1 \ L$ orthophosphoric acid $(H_3PO_4)$ having $70 \%$ purity by weight (specific gravity $1.54 \ g \ cm^{-3}$) is $ . . . . . . $ $M$.
(Molar mass of $H_3PO_4 = 98 \ g \ mol^{-1}$)

How many millimoles of $H^{+}$ ions are present in $100 \, mL$ of $0.6 \, N \, H_3PO_4$?

When $262 \ g$ of xenon (atomic mass $= 131$) reacted completely with $152 \ g$ of fluorine (atomic mass $= 19$),a mixture of $XeF_2$ and $XeF_6$ was produced. The molar ratio $XeF_2 : XeF_6$ is

An unknown chlorohydrocarbon has $3.55\%$ of chlorine. If each molecule of the hydrocarbon has one chlorine atom only,the number of chlorine atoms present in $1\,g$ of chlorohydrocarbon is (Atomic wt. of $Cl = 35.5\,u$; Avogadro constant $= 6.023 \times 10^{23}\,mol^{-1}$)

Which of the following is required to neutralize $1 \ L$ of $1 \ N \ NaOH$?

$56.0 \ L$ of nitrogen gas is mixed with excess of hydrogen gas and it is found that $20 \ L$ of ammonia gas is produced. The volume of unused nitrogen gas is found to be $L$.