Please consider, for a moment, the 1999 Twentieth Century Fox movie "Fight Club." You know that movie, don't you? Edward Norton as the unnamed narrator? Brad Pitt as the seductive subversive, Tyler Durden? Helena Bonham Carter playing a deliciously deviant psycho chick? Lots of sweaty men beating the crap out of each other? Homemade explosives for fun and mayhem? If you've never seen it, I strongly advise watching it.
I would draw your attention to a particular scene that begins approximately 61 minutes and 11 seconds into the movie where, in the rundown kitchen of a rundown house on a rundown street the characters played by Norton and Pitt are making soap. The scene starts with a history lesson and ends with a patch of burnt flesh.
"This is Lye."
Lye, also known as sodium hydroxide or caustic soda, is typically sold as a powder and can be purchased in many hardware stores or online without much fuss. Each sodium hydroxide molecule is made up of one sodium atom (Na), one oxygen atom (O) and one hydrogen atom (H), written by chemists as NaOH. In solution, lye is highly alkaline meaning it has a very high pH (percent hydrogen) value.
Higher pH, between 7 and 14 = alkaline like baking soda
Lower pH, between 1 and 7 = acidic like vinegar
pH of 7 = neutral like water or human blood
Concentrated sodium hydroxide is one of the most powerfully alkaline chemicals you'll ever encounter. An alkaline solution is also known as a "base" which is the opposite of an acid. Remember acids and bases from science class? ("Oh boy! Lemon juice turns blue litmus paper red! Look at that! Ammonia turns red litmus paper blue! My god, this is so lame!!") A refresher on acids and bases later, but for now, back to soap...
The fancy word for the chemical process that produces soap is saponification. You get things started by performing the somewhat hazardous task of mixing a lye solution and then boiling it along with some kind of fat -- be it whale blubber, olive oil, cocoa butter, or (as in "Fight Club") the creamy, bloody flab that's been liposuctioned out of vain rich people. Unwanted byproducts are scooped away and the hot mess is then allowed to cool producing glycerin and a no-frills kind of soap that's solid or liquid depending on the concentrations of the ingredients you added.