Gibb's Free Energy; Pressure Of A Fluid - HP -22S Owner's Manual

Gibb's Free Energy
The change in Gibb's free energy is calculated by the equation:
where G
=
H=
S
=
T=
G=H-TXS
the change in free energy
(~G).
the change in enthalpy
(~.
the change in entropy
(~).
the temperature (in K).
Example: For a certain chemical reaction run at 25 °C, ~ =
-133.1 Kcaljmole and ~ = 3.4 cal/K-mole. Calculate ~G.
Keys: Display: Description:
I
EVALI
H?value
Prompts for H.
133.1
EtJ
I
INPUT I
T?value
Stores H, prompts for
T.
25
G
273.1
I
INPUT I T=298.1
Calculates and stores
T
S?value
(K), prompts for S.
3.4
r
lJG
311NPUTI
G=-134.1135
Stores S (Kcal), calcu-
lates G (Kcal).
Pressure of a Fluid
The equation for calculating the pressure in a column of fluid is:
where D
=
G=
H=
I
=
p=
P=!+DxGxH
the density of the fluid.
the acceleration of gravity.
the height of the column.
the pressure at H
=
O.
the pressure.
102 7: The Equation Library