What is the relationship between viscosity and density?

Identify the correct statements from the following:
$I$. For an ideal gas,the compressibility factor is $1.0$.
$II$. The kinetic energy of $NO_{(g)}$ (molar mass $= 30 \ g \ mol^{-1}$) at $T(K)$ is $x \ J \ mol^{-1}$. The kinetic energy of $N_2O_{4(g)}$ (molar mass $= 92 \ g \ mol^{-1}$) at $T(K)$ is $2x \ J \ mol^{-1}$.
$III$. The rate of diffusion of a gas is inversely proportional to the square root of its density.

Which of the following statements is incorrect?
$1$. The property of liquid drops to have minimum surface area is called surface tension.
$2$. Surface tension of liquids decreases with rise in temperature.
$3$. The $SI$ unit of surface tension is $N \ m^{-1}$.
$4$. Magnitude of surface tension is less,when there is strong attractive force between the molecules.

$A$ box of $1 \, L$ capacity is divided into two equal parts by a thin partition,which are filled with $2 \, g$ of $H_2$ and $16 \, g$ of $CH_4$ respectively. The temperature of each part is $T$. The pressure in each part is $P$. If the partition is removed,the total pressure will be:

Two gases $X$ and $Y$ are taken in equal molar proportions. The ratio of their rates of diffusion is $1 : 2$. What will be the mole fraction of $X$ in a mixture containing $2 \ g$ of $X$ and $3 \ g$ of $Y$?

Which of the following statements is correct?