Sodium hydroxide isn’t super safe ... Chemically, this is the sodium salt of sulphuric acid, and you can dispose of it safely after neutralizing it with baking soda. Rit dye can provide coloring.

The fizzy action is essentially a visual "placebo," formed by the combination of an acid and a base ... common bases include sodium carbonate (washing soda), sodium hydroxide (lye) and ammonia.

Strong acids such as hydrochloric acid, sulfuric acid and nitric acid are ... For example, drain cleaners and oven cleaners usually contain sodium hydroxide. Ammonia is also commonly used in ...