Equal masses of methane and oxygen are mixed in an empty container at $25^\circ C$. The fraction of the total pressure exerted by oxygen is

$1 \text{ mole}$ of concentrated $HCl$ requires $X \text{ moles}$ of dilute $NaOH$ for neutralization,and $1 \text{ mole}$ of concentrated $H_2SO_4$ requires $Y \text{ moles}$ of dilute $NaOH$. Which of the following relations is true?

How many grams of $NaOH$ are required to neutralize $12.2 \ g$ of benzoic acid (in $g$)?

Concentrated $HCl$ is $10 \, N$. How much volume of concentrated $HCl$ is required to prepare $1000 \, mL$ of $1 \, N$ $HCl$ by dilution?

When $500 \, mL$ of a gaseous hydrocarbon is burned with sufficient $O_2$,it produces $2.5 \, L$ of $CO_2$ and $3.0 \, L$ of water vapor. What is the molecular formula of the hydrocarbon?

$2.5 \ cm^{3}$ of $0.2 \ M \ H_{2}SO_{4}$ solution is diluted to $0.5 \ dm^{3}$. Find the normality of the diluted solution. (in $N$)