In the given equation of state for a real gas:
\(\left( P + \frac{a}{V^2} \right) (V - b) = RT,\)
the term \( \frac{a}{V^2} \) must have the same dimensions as pressure \( P \) since it is being added to \( P \).
The dimensional formula of pressure \( P \) is:
\([P] = [F][A^{-1}] = [M][L^{-1}][T^{-2}],\)
where \( F \) is force and \( A \) is area. Therefore, the dimensions of \( \frac{a}{V^2} \) must also be the same as \( P \).
Since \( \frac{a}{V^2} \) has the same dimensions as pressure
The correct option is (D) : P
An ideal gas is a theoretical gas composed of a set of randomly-moving point particles that interact only through elastic collisions.
The ideal gas law states that the product of the pressure and the volume of one gram molecule of an ideal gas is equal to the product of the absolute temperature of the gas and the universal gas constant.
PV=nRT
where,
P is the pressure
V is the volume
n is the amount of substance
R is the ideal gas constant
When we use the gas constant R = 8.31 J/K.mol, then we have to plug in the pressure P in the units of pascals Pa, volume in the units of m3 and the temperature T in the units of kelvin K.