Ammonia on reaction with chlorine forms an explosive $NCl_3$. What is the mole ratio of $NH_3$ and $Cl_2$ required for this reaction?

What is the volume of $CO_2$ in liters produced at $STP$ by the complete decomposition of $9.85 \ g$ of $BaCO_3$? (Atomic mass of $Ba = 137$,$C = 12$,$O = 16$)

$100 \, mL$ of a mixture of $NaOH$ and $Na_2SO_4$ is neutralized by $10 \, mL$ of $0.5 \, M$ $H_2SO_4$. Hence,the mass of $NaOH$ in $100 \, mL$ solution is ........... $g$.

If isobutane and $n$-butane are present in a gas,then how much oxygen should be required for complete combustion of $10 \ kg$ of this gas? (in $kg$)

$50 \ mL$ of $0.5 \ M$ oxalic acid is needed to neutralize $25 \ mL$ of sodium hydroxide solution. The amount in grams of $NaOH$ in $50 \ mL$ of the given sodium hydroxide solution is:

$1.0 \ g$ of pure calcium carbonate was found to require $50 \ mL$ of dilute $HCl$ for complete reaction. The strength of the $HCl$ solution is given by ........ $N$.