Determine Z and V for steam at 250°C and 1,800 kPa by the following: The virial equation (Eq. 3.40) with the following experimental values of virial coefficients: B=-152.5 cm^3 mol^(-1) C=-5,800 cm^6 mol^(-2) The virial equation (Eq. 3.38) with a value of B from the generalized Pitzer correlation (Eq. 3.63). The steam tables (App. F).

Apipe with an outside diameter of 15 cm is exposed to an ambient air and surrounding temperature of -20°c. the pipe has an outer surface temperature of 65°c and an emissivity of 0.85. if the rate of heat loss from the pipe surface is 0.95 kw per meter of length, the external convective heat transfer coefficient (h) is: (a) 12.5 w/m"k (b) 18.6 w/mk (c) 23.7 w/mk (d) 27.9 w/mk (e) 33.5 w/mk