Experimental determination of spreading pressure in monolayers Langmuir balance

2 Experimental determination of spreading pressure in monolayers Langmuir balance 

Incomplete spreading sometimes occurs due to poor selection of spreading conditions. This can be detected by simple visual observation using suitable lamps to illuminate the surface, such as dark-field illumination. The best test for completeness of spreading is the reproducibility of the experimental results. When we are satisfied with the homogeneous monolayer formation, we can start to examine its properties. When the available area for the monolayer is large, the distance between adjacent solute molecules in the monolayer is 

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