What is the molarity of an $H_2SO_4$ solution that has a density of $1.84 \ g/cc$ at $35 \ ^oC$ and contains $98 \ \%$ solute by weight?

The amount of calcium oxide produced on heating $150 \ kg$ of limestone ($75 \%$ pure) is $........... \ kg$ $(Nearest \ integer)$. Given: Molar mass (in $g \ mol^{-1}$) of $Ca = 40, O = 16, C = 12$.

......... $cm^3$ is the volume of $0.1 \ N \ HCl$ required to react completely with $1.0 \ g$ of pure calcium carbonate $(Ca = 40, C = 12, O = 16)$.

$300 \ mL$ of a gaseous hydrocarbon when burnt in excess of $O_2$ gave $2.4 \ L$ of $CO_2$ and $2.7 \ L$ of water vapour under same conditions. The molecular formula of the hydrocarbon is:

The volume of $0.1 \ M \ HCl$ required in $mL$ to neutralise $20 \ mL$ of a solution containing $0.106 \ g$ of $Na_2CO_3$ is

The number of chlorine atoms in $20 \, mL$ of chlorine gas at $STP$ is ..... $\times 10^{21}$. (Round off to the Nearest Integer).
[Assume chlorine is an ideal gas at $STP$,$R = 0.083 \, L \, bar \, mol^{-1} \, K^{-1}$,$N_{A} = 6.023 \times 10^{23}$]