4-54 4-102 Methane is heated in a rigid container. The final pressure of the methane is to be determined using the ideal gas equation and the Benedict-Webb-Rubin equation of state. Analysis (a) From the ideal gas equation of state, P2 P1 T2 T1 (100 kPa) 673 K 293 K Methane 100 kPa 229.7 kPa 20qC The specific molar volume of the methane is v1 v 2 Ru T1 P1 (8.314 kPa m 3 /kmol K)(293 K) 100 kPa Q 24.36 m 3 /kmol (b) The specific molar volume of the methane is v1 v 2 Ru T1 P1 (8.314 kPa m 3 /kmol K)(293 K) 100 kPa 24.36 m 3 /kmol Using the coefficients of Table 4-4 for methane and the given data, the Benedict-Webb-Rubin equation of state for state 2 gives RuT2 P2 v2 § J · C · 1 bR T a aD c § ¨¨ B0 RuT2 A0 02 ¸¸ 2 u 23 6 3 2 ¨1 2 ¸ exp(J / v 2 ) v v v v v T T © ¹ 2 ¹ 2 © (8.314)(673) §¨ 2.286 u106 ·¸ 1 0.003380u 8.314 u 673 5.00 0.04260 u 8.314 u 673 187.91 2 2 ¨ ¸ 24.36 673 24.363 © ¹ 24.36 5.00 u 1.244 u104 2.578 u105 § 0.0060 · 2 ¨1 ¸ exp(0.0060 / 24.36 ) 24.366 24.363 (673)2 © 24.362 ¹ 229.8 kPa PROPRIETARY MATERIAL. © 2008 The McGraw-Hill Companies, Inc. Limited distribution permitted only to teachers and educators for course preparation. If you are a student using this Manual, you are using it without permission.

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# 4-54 the ideal gas equation and the Benedict-Webb-Rubin equation of state. Methane