Total number of moles for the reaction $2HI \rightleftharpoons H_2 + I_2$ at equilibrium,if $\alpha$ is the degree of dissociation,is:

The vapour density of $PCl_5$ at $25^{\circ}C$ is $100$. Calculate the degree of dissociation at this temperature.

Gaseous $N_2O_4$ dissociates into gaseous $NO_2$ according to the reaction:
$N_2O_{4(g)} \rightleftharpoons 2NO_{2(g)}$
At $300 \ K$ and $1 \ atm$ pressure,the degree of dissociation of $N_2O_4$ is $0.2$. If one mole of $N_2O_4$ gas is contained in a vessel,then the density of the equilibrium mixture is.......$g/L$

The density of air at $N.T.P.$ is $0.001293 \ g \ mL^{-1}$. Its vapor density is .....

Vapour density of a gas is $5.6$,volume of $5.6 \ g$ of it at $STP$ is ............... $L$

Which of the following equations is correct for the vapour density of completely dissociated ammonium chloride?