When liquid and vapor coexist in a container at equilibrium, the pressure is called vapor
pressure. Several models predict vapor pressure. One, called the Antoine equation , first
introduced by Ch. Antoine in 1888, yields vapor pressure in units of millimeters of mercury [mm Hg].
The constants A , B , and C are called the Antoine constants ; they depend on both fluid type
and temperature. Note that “ B ” and “ C ” must be in the same units as temperature and “A ”
is a dimensionless number, all determined by experiment.
Create a worksheet using the provided template. The Antoine constants, located in cells
D17 to I24 of the workbook provided, should automatically fill in after the user selects one
from a drop-down menu in Cell A9 of the compounds shown below. (Hint: Use data validation and lookup expressions.)
Next, create a column of temperature ( T ) beginning at −100 degrees Celsius and
increasing in increments of 5 degrees Celsius until a temperature of 400 degrees Celsius.
In column B, calculate the vapor pressure ( P , in millimeters of mercury, [mm Hg]) using
the Antoine equation, formatted to four decimal places. If the equation is outside the valid
temperature range for the compound, the pressure column should be blank.