How does drain cleaners work?

-Karthik Gurumurthy

Drain cleaners are usually alkaline solutions when dissolved in water. Most of these drain cleaners have sodium hydroxide as an active ingredient (either the solid or liquid form of sodium hydroxide).Grease dissolves in basic (alkaline) solutions (Solutions of pH over 7).  Alkalinity of these cleaners is responsible for the dissolution of grease that has clogged drains and plumbing.  I have seen few drain cleaners that contain solid aluminum particles which react with an alkaline solution to produce hydrogen gas and release heat. The turbulence of evolving gas and the release of heat during the chemical reaction creates additional forces to open up drains.