How much solid oxalic acid (Molecular weight $126$) has to be weighed to prepare $100 \ mL$ of exactly $0.1 \ N$ oxalic acid solution in water (in $g$)?

$1 \ g$ of a carbonate $(M_2CO_3)$ on treatment with excess $HCl$ produces $0.01 \ mol$ of $CO_2$. The molar mass of $M_2CO_3$ is $.......... \ g \ mol^{-1}$. (Nearest integer)

What is the quantity of hydrogen gas liberated when $46 \ g$ sodium reacts with excess ethanol? (Given Atomic mass of $Na = 23$)

$100 \ mL$ of $H_{2(g)}$ and $100 \ mL$ of $Cl_{2(g)}$ were allowed to react at $1 \ bar$ pressure as: $H_{2(g)} + Cl_{2(g)} \longrightarrow 2 HCl_{(g)}$. What will be the $PV$ type of work done during the reaction?

For the combustion reaction of $1 \, mol$ of a hydrocarbon $C_xH_y$,the coefficients of $O_2$,$CO_2$,and $H_2O$ involved are respectively:

Volume of $\frac{N}{10}$ $H_2SO_4$ required to neutralize $10 \ mL$ of $5 \ N$ $Na_2CO_3$ is.....$mL$.