TABLE OF CONTENTS Avinash Gupta, Ph.D.
Senior Principal Chemical Engineer
Chevron Lummus Global
Bloomfield, NJ
Calculate the molar gas constant R in the following units:
(atm)(cm 3)/(g mol)(K)
(psia)(ft 3)/(lb mol)( R)
(atm)(ft 3)/(lb mol)(K)
kWh/(lb mol)( R)
hp h/(lb mol)( R)
(kPa)(m 3)/(kg mol)(K)
cal/(g mol)(K)
1. Assume a basis. Assume gas is at standard conditions, that is, 1 g mol gas at 1 atm (101.3 kPa) pressure and 0 C (273 K, or 492 R), occupying a volume of 22.4 L.
2. Compute the gas constant. Apply suitable conversion factors and obtain the gas constant in various units. Use PV=RT; that is, R=PV/T. Thus,
R=(1 atm)[22.4 L/(g mol)](1000 cm 3/L)/273 K=82.05 (atm)(cm 3)/(g mol)(K)
R=(14.7 psia)[359 ft 3/(lb mol)]/492 R=10.73 (psia)(ft 3)/(lb mol)( R)
R=(1 atm)[359 ft 3/(lb mol)]/273 K=1.315 (atm)(ft 3)/(lb mol)(K)
R=[10.73 (psia)(ft 3)/(lb mol)( R)](144in 2/ft 2)[3.77 10 ?7 kWh /(ft Ibf)]=5.83 10 ?4 kWh/ (lb mol)( R)
R=[5.83 10 ?4 kWh/(lb mol)( R)](1/0.746 hp h/kWh)=7.82 10 ?4 hp h/(lb mol)( R)
R=(101.325 kPa/atm)[22.4 L/(g mol)][1000 g mol/(kg mol)]/(273 K)(1000 L/m 3) = 8.31 (kPa)(m 3)/(kg mol)(K)
R=[7.82 10 ?4 hp h/(lb mol)( R)][6.4162 105 cal/(hp h)][1/453.6 lb mol/(g ...
