Fugacity and pressure are numerically equal, when the gas is
A
In standard state
B
At high pressure
C
At low temperature
D
In ideal state
Correct Answer: In ideal state
We know the concept of fugacity is originated from the equation $$d{\mu _i} = pdv - sdT$$ for an pure gas.Under constant temperature and assuming an ideal gas we can write this as $$d\mu = RTdlnP$$ and for an real gas the same equation is assumed keeping all the non-ideality in the term fugacity and written as $$d\mu = RTdlnf$$
So, we can say for an ideal gas $$f = p.$$
