Dish soap is a great example of a wetting agent. With all the food oils and such on the plate cohesive forces make it difficult for the water to spread and clean the plate. The soap dissolves all theses unwanted particles, exposing a clean surface. The soap also lowers the surface tension of water, allowing it to spread evenly across the entire surface.
There are four main types of wetting agents: anionic, cationic, amphoteric, and nonionic.
• Anionic, cationic, and amphoteric wetting agents ionize when mixed with water.
• Anions have a negative charge, while cations have a positive charge.
• Amphoteric wetting agents can act as either anions or cations, depending on the acidity of the solution.
• Nonionic wetting agents do not ionize in water. A possible advantage for using a nonionic wetting agent is that it does not react with other ions in the water, which could lead to formation of a precipitate.