5/23/2018 Chee 210 Tutorial Set 6

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CHEE 210 Tutorial Set 6

1. Liquid isobutane is throttled through a valve from an initial state of 360 K, 4000 kPa,

and 132 cm3/mol, to a final state of 2000 kPa. Estimate the temperature change and

the entropy change of the isobutane. The volume expansivity of isobutane can beassumed to be 4.082(10-3) K-1, and its heat capacity is 2.78 J/(g K).

2. Estimate the entropy change of vaporization of benzene at 50C. The vapor pressure of

benzene is given by:

lnPsat

=15.90082788.51

T52.36 where P is in mm Hg, and T in K.

For benzene, = 0.21, Tc= 562.2 K, Pc= 48.98 atm.

5/23/2018 Chee 210 Tutorial Set 6

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