PE7.1. Write down in your homework that we will use the words "activity coefficient" in place of "fugacity coefficient", to describe real gases. Write there too that the activity coefficient, gi, just equals the fugacity coefficient, and the activity for a real gas equals: ai=gi(Pi/P0). Use gi to write an expression for the chemical potential of a real gas at partial pressure Pi. Write an example that shows how gi, if known, is used in equilibrium constant calculations