Question

The superheated water vapor is at 15 MPa and 350°C. The gas constant, the critical pressure, and the critical temperature of water are R = 0.4615 kPa·m3/kg·K, Tcr = 647.1 K, and Pcr = 22.06 MPa. Determine the specific volume of superheated water based on the ideal-gas equation. (You must provide an answer before moving to the next part)

Answer 1

Answer:

0.01917 m^3/kg.

Explanation:

Given:

P = 15 MPa

= 1.5 × 10^4 kPa

T = 350 °C

= 350 + 273

= 623 K

Molar mass of water, m = (2 × 1) + 16

= 18 g/mol

= 0.018 kg/mol

R = 0.4615 kPa·m3/kg·K

Using ideal gas equation,

P × V = n × R × T

But n = mass/molar mass

V = (R × T)/P

V/M = (R × T)/P × m

= (0.4615 × 623)/1.5 × 10^4

= 0.01917 m^3/kg.