3L. Surface Tension using the equation 3.28 Back to Main
Equation (3.28) =
-
Where: s = surface tension, (1 dynes/cm = 0.001 N/m)
P = parachor
M = molecular weight of the liquid
=
liquid density, g/cm³
=
vapor density, g/cm³, the density of the vapor in contact with the liquid
The quantity P is estimated by the following equation P = 300 + (2.25)(MW – 100) for mixtures
having a MW greater than 100
If the liquid is a paraffin liquid click on the paraffin liquid box so that a check mark is placed inside of it. Once that is done the quantity P is estimated by the following equation 20° C [68° F] P = 40 + (2.6)(MW) for paraffins, and mixtures to a mol wt of 100
To calculate the surface tension the Liquid Density, Vapor Density, Average Molecular Weight, and whether it is a Paraffin Mixture must be entered into their entry spaces. To do so, use the mouse to click the curser into the entry space and input the data. Once this has been done, select Run to execute the solution.
To convert unit values of data, please refer to “Set Auto Convert and Unit Conversion” in the main page.