What is the vapor density of a mixture containing $20\%\, NO_2$ by volume and $N_2O_4$?

In a $100 \ L$ vessel,$3 \ moles$ of nitrogen and $3 \ moles$ of $PCl_5$ are taken and heated to $500 \ K$. The equilibrium pressure is $3.28 \ atm$. The percentage degree of dissociation of $PCl_5$ is : (Assume ideal behaviour for all gases).

At $NTP$,$5.6 \ L$ of a gas weighs $8 \ g$. The vapour density of the gas is:

At temperature $T$,the dissociation equilibrium of $AB_{2(g)}$ is given as: $2AB_{2(g)} \rightleftharpoons 2AB_{(g)} + B_{2(g)}$. If the degree of dissociation $x$ is very small compared to $1$,then the expression for the equilibrium constant $K_p$ in terms of $x$ and total pressure $P$ is:

At $200 \, ^\circ C$,the observed vapour density $(V.D.)$ of $PCl_5$ is $60$. The degree of dissociation $(\alpha)$ of $PCl_5$ is ..........$\%$ (Given: Molar mass of $PCl_5 = 208.5 \, g/mol$).

If $PCl_5$ undergoes $80\%$ dissociation at $250 \, ^\circ C$,what is its vapour density at this temperature?