For water vapor at 1 bar in the ideal gas state 3 4 2 3.47 1.45 10 1.21 10 p ig c t t r        water vapor obeys the truncated, simplified virial equation 1 p bp rt rt    , where b is a function only of t given by 0 1 c bp b b rt   with 0 1.6 0.422 0.083 r b t   , 1 4.2 0.172 0.139 r b t   , and r c t t t 

a) calculate the value of h2-h1 for superheated steam between the two states p2=100 bar, t2=320 ºc and p1=100 bar and t1= 650 ºc.

b) compare your answer with the value from the steam tables, which is -961.2 j/g.

c) calculate the value of gr for one mole of water at 100 bar at both 320 ºc and 650 ºc. d) compare your answer to the value of g obtained from the steam tables. e) calculate the fugacity of the water vapor in the two states.