What is the relationship between viscosity and density?

Under the same $P$ and $T$,which of the following pairs of gases will diffuse at the same rate through a small jet?

$A$ mixture of equal masses of $SO_2$,$CH_4$,and $O_2$ is taken in an empty container at $298 \, K$. If the total pressure is $2.1 \, atm$,the partial pressure of $CH_4$ in the mixture will be .......... $atm$.

Based on the given figure,the number of correct statement/s is/are $........$.
$A.$ Surface tension is the outcome of equal attractive and repulsion forces acting on the liquid molecule in bulk.
$B.$ Surface tension is due to uneven forces acting on the molecules present on the surface.
$C.$ The molecule in the bulk can never come to the liquid surface.
$D.$ The molecules on the surface are responsible for vapour pressure if the system is a closed system.

Which one of the following equations represents the variation of viscosity coefficient $(\eta)$ with temperature $(T)$?

Indicate the correct statement for a $1 \ L$ sample of $N_{2(g)}$ and $CO_{2(g)}$ at $298 \ K$ and $1 \ atm$ pressure.