What is the pressure of $2 \, mol$ of $NH_3$ at $27 \, ^oC$ when its volume is $5 \, L$ using the van der Waals equation (in $, atm$)? ($a = 4.17 \, L^2 \, bar \, mol^{-2}$,$b = 0.03711 \, L \, mol^{-1}$)

If the inversion temperature of a gas is $-80\,^{\circ}C$,then it will produce cooling under the Joule-Thomson effect at ............... $K$.

$A$ real gas would be most likely to obey the ideal gas laws at

Under which conditions does the $van \ der \ Waals$ equation reduce to the ideal gas equation?

The relation between pressure exerted by an ideal gas $(P_{ideal})$ and observed pressure $(P_{real})$ is given by the equation
$P_{ideal} = P_{real} + \frac{an^2}{V^2}$
$(i)$ If pressure is taken in $N \ m^{-2}$,number of moles in $mol$,and volume in $m^3$,calculate the unit of $a$.
$(ii)$ What will be the unit of $a$ when pressure is in atmosphere and volume in $dm^3$?

The temperature at which a real gas obeys ideal gas laws over an appreciable range of pressure is called ..........