No, the formation of soap scum is not a chemical change. Soap scum appears as the result of a physical change. Some of the soap and whatever has become incorporated into the soap and water dry. After the water is gone, the things left are from the soap and whatever mixed with the soap when it was "working" at cleaning.
Soap scum is a substance, not a change; but the formation of scum is a chemical process.
Soap scum is actually what you get when soap combines with minerals in your water which forms a chemical reaction. It is not bacteria or mold but it can be a house for bacteria to multiply and live. Some soap formulas leave more soap scum than others but they don't deposit bacteria or mold. Bleach is a great product for killing this bacteria and scum.
Zest leaves little scum.
Scrubbing Bubbles Soap Scum Remover is great at removing soap scum from your glass shower doors.
The cast of Soap Scum - 2005 includes: Thom Rivera as Pedro
To remove soap scum off a slate shower you will need a soap scum remover cleaning product. This is the best and easiest way to remove the scum. Some people use a bar of glycerin soap and have success. However, this will make the cleaning process longer.
Borax is the best cleaning product to remove soap scum and mildew.
Soap Scum - 2005 was released on: USA: 15 October 2005 (Bare Bones Film Festival)
Soap Scum - 2004 was released on: USA: 15 June 2004 (Dances With Films Festival of the Unknowns)
get kaboom or some other soap scum cleaning agent. then follow the directions on the bottle.