Surface tension and wettability are important physical properties that play a significant role in the effectiveness of agrochemicals.
The method to calculate the surface tension component is defined in ISO 19403-5:2017 standard.
Surface tension can be measured with force tensiometer using Du Noüy ring or Wilhelmy plate. Or with optical tensiometer using the pendant drop method.
Du Noüy method utilizes the interaction of a platinum ring with the surface of the liquid.