Volume of water needed to mix with $10 \ mL$ of $10 \ N \ HNO_3$ to get $0.1 \ N \ HNO_3$ is ............ $mL$.

The neutralization occurs when $10 \, mL$ of $0.1 \, M$ acid $A$ is allowed to react with $30 \, mL$ of $0.05 \, M$ base $M(OH)_2$. The basicity of the acid $A$ is $...$ $[M$ is a metal$]$

If isobutane and $n$-butane are present in a gas,then how much oxygen should be required for complete combustion of $10 \ kg$ of this gas? (in $kg$)

What amount of conc. $H_2SO_4$ solution should be used to prepare $500 \ mL$ of $0.5 \ M \ H_2SO_4$ (in $g$)? (The concentration of $H_2SO_4$ solution being used is $90\%$ and molecular mass of $H_2SO_4 = 98.079 \ g \ mol^{-1}$)

Reaction of $x \ g$ of $Sn$ with $HCl$ quantitatively produced a salt. The entire amount of the salt reacted with $y \ g$ of nitrobenzene in the presence of the required amount of $HCl$ to produce $1.29 \ g$ of an organic salt (anilinium chloride) quantitatively.
$(1)$ The value of $x$ is. . . . .
$(2)$ The value of $y$ is. . . . .

$A$ solution of $H_2SO_4$ is $31.4 \%$ $H_2SO_4$ by mass and has a density of $1.25 \ g \ mL^{-1}$. The molarity of the $H_2SO_4$ solution is . . . . . . $M$ (nearest integer) [Given molar mass of $H_2SO_4 = 98 \ g \ mol^{-1}$]