What is the weight of oxygen required for the complete combustion of $2.8 \, kg$ of ethylene? (in $kg$)

When $10 \ mol$ of $SO_2$ and $15 \ mol$ of $O_2$ are mixed and passed over a catalyst,$8 \ mol$ of $SO_3$ is formed. How many moles of $SO_2$ and $O_2$ remain unreacted?

At $STP$,$4.4 \ g$ of an unknown gas occupies a volume of $2.24 \ L$. What is the gas?

Equal volumes of $0.1 \ M$ $AgNO_3$ and $0.2 \ M$ $NaCl$ are mixed. The concentration of $NO_3^-$ ion in the mixture will be ............ $M$.

The masses of carbon dioxide and water (in $g$) respectively formed during complete combustion of $10 \ g$ of glucose at $STP$ are

Assuming complete decomposition,the volume of $CO_2$ released at $STP$ on heating $9.85 \ g$ of $BaCO_3$ (Atomic mass of $Ba = 137$) will be ................ $L$.