$X \ g$ of benzoic acid on reaction with aqueous $NaHCO_3$ releases $CO_2$ that occupies $11.2 \ L$ volume at $STP$. The value of $X$ is . . . . . . $g$.

The mass of iron converted into $Fe_3O_4$ by the action of $18\text{ g}$ of steam is : (Given: Molar mass of $H$, $O$ and Fe are $1$, $16$ and $56\text{ g mol}^{-1}$ respectively). Assume iron is present in excess: (in $\text{ g}$)

Methylation of $10 \ g$ of benzene gave $9.2 \ g$ of toluene. Calculate the percentage yield of toluene $......$. (Nearest integer)

What fraction of $Fe$ exists as $Fe(III)$ in $Fe_{0.96}O$?
(Consider $Fe_{0.96}$ to be made up of $Fe(II)$ and $Fe(III)$ only)

One third litre of $x \ M \ K_2Cr_2O_7$ is required to completely oxidise $2 \ L$ of $0.1 \ M$ ferrous ammonium sulphate in acidic medium. What is $x$?

How many moles of $H_2O$ (per mole of $Cl_2$ evolved) will be formed when $KMnO_4$ is added to $HCl$ solution?