What volume in $mL$ of $73 \ g/L$ hydrochloric acid is required to completely neutralize the sodium hydroxide produced by the reaction of $0.46 \ g$ of sodium metal with water?

$20 \ mL$ of sodium iodide solution gave $4.74 \ g$ silver iodide when treated with excess of silver nitrate solution. The molarity of the sodium iodide solution is $........ M$. $(Nearest \ Integer \ value)$
$(Given: Na=23, I=127, Ag=108, N=14, O=16 \ g \ mol^{-1})$

In the bromination of propyne,$1,1,2,2-$tetrabromopropane is obtained in $27\%$ yield. The amount of $1,1,2,2-$tetrabromopropane obtained from $1 \; g$ of bromine $(Br_2)$ in this reaction is $\dots \; \times 10^{-1} \; g$. (Nearest integer)
(Molar mass: Bromine $(Br)$ $= 80 \; g/mol$)

What is the volume (in $dm^3$) occupied by $75 \ g$ of ethane at $S$.$T$.$P$.?

Dissolving $1.24 \ g$ of white phosphorus in boiling $NaOH$ solution in an inert atmosphere gives a gas $Q$. The amount of $CuSO_4$ (in $g$) required to completely consume the gas $Q$ is. . . . [Given: Atomic mass of $H = 1, O = 16, Na = 23, P = 31, S = 32, Cu = 63$]

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