$80 \ mL$ of $O_2$ takes $2 \ minute$ to pass through a hole. What volume of $SO_2$ will pass through the same hole in $3 \ minute$?

The radius of the $Na^{+}$ ion is $95 \ pm$ and that of $Cl^{-}$ ion is $181 \ pm$. Predict the coordination number of $Na^{+}$ in $NaCl$.

If hydrogen gas travels a distance of $10.5 \ cm$ in $5 \ s$ through a long narrow tube at a pressure of $1 \ atm$,what distance (in $cm$) will oxygen gas travel in $5 \ s$ at a pressure of $2 \ atm$?

Which of the following is a superfluid?

Assertion : Wet air is heavier than dry air.
Reason : The density of dry air is more than density of water.

At $298 \ K$, a flask '$A$' of unknown volume $(V)$ contains oxygen at $5 \ atm$. Another flask '$B$' of volume $2 \ L$ contains helium at $3 \ atm$. Two flasks are connected together by a small tube of zero volume. After the two gases are completely mixed, if the resulting mixture is found to have the mole fraction of oxygen as $0.2$, the volume of flask '$A$' (in $L$) is (Assume oxygen and helium as ideal gases)