How much volume of water is to be added to dilute $10 \, mL$ of $10 \, N \, HCl$ to make it decinormal? .............. $mL$

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 $H_3PO_4 = 98 \ g \ mol^{-1}$)

When $100 \, g$ of $CaCO_3$ reacts with $1 \, N \, HCl$,how many grams of $CO_2$ will be obtained upon completion of the reaction?

How many litres of oxygen (at $STP$) are required for complete combustion of $39 \ g$ of liquid benzene?
(Atomic weights: $C=12, O=16, H=1$)

Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at $STP$ from the reaction of $11.5 \ g$ of zinc with excess $HCl$ is $.......... \ L$ (Nearest integer) (Given: Molar mass of $Zn$ is $65.4 \ g \ mol^{-1}$ and Molar volume of $H_2$ at $STP = 22.7 \ L$)

What volume in $mL$ of $96\% \, w/w \, H_2SO_4$ is required to prepare $2 \, L$ of $3 \, M \, H_2SO_4$ solution? (Density of $H_2SO_4$ solution $= 1.83 \, g/mL$)