On Mon, 07 May 2007 14:06:48 -0500, Richard J Kinch
wrote:

Doug Miller writes:

You go right ahead and do that if you want, but advising others of the
(supposed) safety of a practice that every chemistry instructor and
laboratory safety guide warns against, is stupid and irresponsible.

The advice is sound for sulfuric acid. For hydrochloric, it is just
superstition spread by repetition. To their credit, not "every chemistry
instructor" or guide is quite so credulous, although generally they do
spout this "conventional wisdom." But it is just wrong in being
overgeneralized to all acids.


It's a generalized rule for mixing water and any acid. It may not
be neccessary in the case of HCl, but since being consistant doesn't
cost you anything and does reduce the chance of getting it wrong
with other acids, most people just tell you to do it that way always.
There is simply no value in itemizing the exceptions. Especially
when you're trying to half-train a classfull of ignorant savages
like HS/college students who don't want to be there and don't
care, anyway.