What is the purpose of using a dispersant in soil testing?

Using a dispersant in soil testing is essential for promoting the separation of soil particles. In soil analysis, particularly in tests like sedimentation analysis or particle size distribution, soil samples often contain clumps or aggregates. These aggregates can interfere with obtaining accurate measurements of the individual particles' sizes and distribution.

By adding a dispersant, the surface tension among the soil particles is reduced, which allows these particles to separate and disperse uniformly throughout a liquid medium. This uniform distribution is crucial for achieving precise and reliable results when analyzing the soil's physical properties, such as its texture, grading, or classification. The ability to effectively separate particles ensures that the testing methods yield data reflective of the true characteristics of the soil sample.