so wait one second. what exactly is the difference between the active ingredients in clothes detergent versus dish soap, or dish soap versus shampoo, or whatever.
are there specific surfacents for each job, or are they basically the same (ignoring for a moment all of the blood-removing enzymes and whatnot).
have we been, pardon the pun, brainwashed to believe these are all very different soaps, when in fact it’s one spigot spurting into various bottles?
And, aren’t all soaps also detergents and surficants. Isn’t it all a continuum rather than real categories?
Soaps are made from natural fatty acids (traditionally from beef tallow) and a base (traditionally lye). The pH is basic. Their major shortcoming is the formation of soap scum. Detergents are synthetic, and are (or at least were) made from petroleum and not natural fats. The pH is neutral.
The most common detergents nowadays are completely synthetic. They generally include sodium lauryl sulfate or sodium laureth sulfate (which is not the IUPAC name, and I have no idea what it actually is), or a combination of both. Sodium lauryl sulfate is also known as sodium dodecyl sulfate, or SDS, and it’s used in laboratories (including the one in which I work) to denature and solubilize protein–which is what it does on your skin’s surface, as well. Shampoo and soap almost always contain these or very similar ingredients; I can’t say for certain about laundry detergent, but given its consistency (especially examining the fragrance/dye-free detergents) compared against the SDS we use in the lab, I’d guess that it they’re not the same thing, they’re similar.
Also note that dish soaps and laundry soaps often contain what are labeled on the bottle as “nonionic surfactants”–which are chemicals such as lauroylsarcosine and the “Triton” reagents that act as detergents–albeit milder ones–without any of the pesky pH problems of other detergents, since they don’t ionize. The pH of the lauryl sulfates and related compounds is slightly basic.
For the grand finale, the major active ingredient found in rust and lime removers such as CLR, or the soap-scum stuff you spray on your tiles after every shower, tends to be EDTA (ethylenediaminetetraacetate), which gloms onto the zinc and calcium and iron and so forth and makes it soluble.
Any other questions? 
LL <–showing his chemistry background
Laundry Det also has “briteners”, which make the clothes appear brighter. However, in a pinch, yes you can wash your clothes in dish det, or even soap. In my college days, i found that just baking soda did a very fair job, got rid of the smells, anyway.