On May 21, 2:20 pm, basskisser wrote:

Seeing how the definition of "soap" is simply a surfactant,

But that's not a really GOOD definition, just a colloquial one, for
either term. For instance, the Charlie's soap site explains that it
got that name colloquially and retains it from familiarity. Hard to
beat a 4 letter word.

Also be aware that in Index Medicus (NLM) and in some other medical
contexts, the contraction "surfactant" applies specifically to
PULMONARY surfactant, while "surface active agent" retains the more
general meaning.

There are also some soaps that aren't very soapy and, practically,
aren't surfactants at all. For instance, a dietary supplement might
supply potassium as potassium acetate, which technically is a soap but
has no useful amount of surface activity.

Robert

wrote:
:On May 21, 2:20 pm, basskisser wrote:

: Seeing how the definition of "soap" is simply a surfactant,

:But that's not a really GOOD definition, just a colloquial one, for
:either term. For instance, the Charlie's soap site explains that it
:got that name colloquially and retains it from familiarity. Hard to
:beat a 4 letter word.

:Also be aware that in Index Medicus (NLM) and in some other medical
:contexts, the contraction "surfactant" applies specifically to
:PULMONARY surfactant, while "surface active agent" retains the more
:general meaning.

:There are also some soaps that aren't very soapy and, practically,
:aren't surfactants at all. For instance, a dietary supplement might
:supply potassium as potassium acetate, which technically is a soap but
:has no useful amount of surface activity.

For instance, lubricating greases are mostly soap based, mostly
calcium or lithium. It's a big advantage that they're not
water-soluble.