68. Using the data below, find out the mutual spreadability of the specified substance and water. In case of non-spreading, check whether one substance wets the other and, if so, determine the contact angle of wetting. The surface tension of water at 20°C is 72.75∙10-3 N/m.
Substance: engine oil
σl/g , mN/m: 32.60
σl/water, mN/m: 29.00

If you do not open the file - install the RAR archiver. Inside the archive you will find a solution in Word format.