Name: __________________________________
Score _________________
BME 100L
Fall 2009
Exam 2
1. A bubble containing 3 mol of an ideal gas is formed in the water. Initially, it is located at 10
meter below the surface of water. The air pressure (P
0
) above the water is 1 atm. Based on what
you have learned in physics, the pressure in the water at depth h is equal to
gh + P
0
, where
is
the water mass density (1 g/cm
3
) and g is the acceleration of gravity (9.8 m/sec
2
). Since the mass
density of gas is much smaller than 1 g/cm
3
, the bubble will spontaneously move up in the water.
Assume that there is no mixing between gas and liquid water and the temperature is 15
o
C in both
gas and water. When the bubble reaches the water surface, determine:
(a)
E,
H,
S, and
G,
(b) the maximum amount of work that the gas could do on the liquid water.
Note: 1 atm = 1.0133*10
6
g/(cm sec
2
)
Solution:
(a)
(6 points)
E =
H = 0 since T = constant
2
1
1
2
1
1
1
P
P
ln
nR
V
V
ln
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
 Fall '07
 YUAN
 Enthalpy, Energy, 1 K, Standard enthalpy change of formation

Click to edit the document details