What is meant by payload?

At $100\,^oC$ and $1\, atm$ pressure,the density of liquid water is $1.0\, g\, cm^{-3}$ and the density of water vapor is $0.0006\, g\, cm^{-3}$. What is the volume occupied by water molecules in $1\, L$ of steam at the same temperature in $cm^3$?

What is the boiling point of $SO_2$ gas (in $K$)?

Air contains $70\% \, N_2, \, 20\% \, O_2$ and $1\% \, CO_2$ by volume. If the total pressure of air is $1 \, bar$,find the partial pressure of $N_2, O_2$ and $CO_2$.

Explain the absolute temperature scale.

At $T \ K$,equal weights of $H_2, D_2$,and $T_2$ are present in a closed vessel. The pressure exerted by this gaseous mixture is $P \ atm$. The ratio of partial pressures of $T_2, D_2$,and $H_2$ is approximately. ($H, D$ and $T$ are isotopes of hydrogen).