The reaction of fats or oils with sodium hydroxide (NaOH) or potassium hydroxide (KOH) produces soap and glycerol. This process is called saponification.

Here's a breakdown:

* Fats and oils are triglycerides, which are esters of glycerol and long-chain fatty acids.

* Sodium hydroxide (NaOH) or potassium hydroxide (KOH) are strong bases.

* When these bases react with triglycerides, they break the ester bonds, releasing glycerol and forming salts of fatty acids. These salts are what we know as soap.

The chemical equation for saponification is:

Triglyceride + 3 NaOH → Glycerol + 3 Soap (sodium salt of fatty acid)

In summary:

* Reactants: Fats/oils (triglycerides) and NaOH/KOH.

* Products: Soap and glycerol.