A dispersant is a substance that is used to disperse or break up oil or other hydrocarbon spills on water surfaces.It is typically a liquid chemical that is sprayed onto the oil slick, causing the oil to break up into smaller droplets.This allows the oil to mix more easily with the surrounding water, enhancing its natural dispersion and degradation by bacteria and other microorganisms.Dispersants are commonly used in oil spill response efforts to minimize the environmental impact of spills and facilitate their cleanup.