$23 \ g$ of sodium metal is reacted with water. Find the volume of $H_2$ gas evolved at $STP$ in $mL$.

$100 \, mL$ of $0.1 \, N \, HCl$ is neutralized by $0.2 \, N \, NaOH$ solution. After adding $30 \, mL$ of $NaOH$ solution,the neutralization is continued using $0.25 \, N \, KOH$. Calculate the volume of $KOH$ in $mL$ required to complete the neutralization.

For the combustion reaction of $1 \ mol$ of benzene,if all reactants and products are in the gaseous state,then $\Delta n_{(g)}$ is equal to ......

$A$ flask is weighed when filled with methane $(CH_4)$. The methane is then removed,and the flask is weighed again. When the flask is filled with oxygen $(O_2)$ at the same temperature and pressure,the mass of oxygen will be:

$A$ solution of $20.2 \, g$ of $1,2$-dibromopropane in $MeOH$ upon heating with excess $Zn$ produces $3.58 \, g$ of an unsaturated compound $X$. The yield $(\%)$ of $X$ is closest to [Atomic weight of $Br$ is $80$].

The volume of hydrogen liberated at $STP$ by treating $2.4 \ g$ of magnesium with excess of hydrochloric acid is $x \times 10^{-2} \ L$. Find the value of $x$. Given: Molar volume of gas is $22.4 \ L$ at $STP$. Molar mass of magnesium is $24 \ g \ mol^{-1}$.