Is Acid Caustic?
David J Camp
people getting acid burns or being disinterated with acid, such
as an old superman series where a criminal tried to use the Statute of
Limitations law to avoid prosecution by sealing himself in a concrete
chamber that could only be breached by the application of an acid.
I am guessing that bases (hydroxides) are much more caustic than acid.
We know of many ways that people expose themselves to acid without
harm. People drink lemonade and enjoy it immensely. Can you get Real
Lemon on your skin without harm? People are known to have highly
acidic stomachs without melting down.
I propose that perhaps acid becomes caustic in glass because the stray
hydrogen ions are absorbed by the glass, leaving more caustic
chemicals in solution. -David-
# da...@wubios.wustl.edu David J. Camp BS MS ^ #
# da...@campfire.stl.mo.us +1 314 382 0584 < * > #
# I am a member of: The League for Programming Freedom. v #
# abs (investment#1 - investment#2) << abs (anyinvestment - anydebt) #
Keith Warren Rickert
>We observe that acid has an affinity for glass. We hear tales of
>people getting acid burns or being disinterated with acid, such
>as an old superman series where a criminal tried to use the Statute of
>Limitations law to avoid prosecution by sealing himself in a concrete
>chamber that could only be breached by the application of an acid.
>I am guessing that bases (hydroxides) are much more caustic than acid.
>We know of many ways that people expose themselves to acid without
>harm. People drink lemonade and enjoy it immensely. Can you get Real
>Lemon on your skin without harm? People are known to have highly
>acidic stomachs without melting down.
>I propose that perhaps acid becomes caustic in glass because the stray
>hydrogen ions are absorbed by the glass, leaving more caustic
>chemicals in solution. -David-
Uh, no.
I dont know what you mean by acid having an affinity for glass.
Acid stored in plastic bottles is just as caustic as that stored
in glass bottles.
The key is the strength of the acid; mildly acidic solutions
such as lemon juice wont cause any harm. Similarly, mildly basic
solutions such as a solution of sodium bicarbonate in water
arent a problem.
As far as your stomach goes, it is specifically designed to be
resistant to acid, by coating itself in a protective mucus layer.
Stomach fluids will be irritating to other parts of the body.
Glass doesnt absorb a significant amount of hydrogen ions from
even a fairly dilute acid solutions.
Keith
--
Keith Rickert |
ke...@imppig.caltech.edu | "death - the undiscovered country from
ric...@cco.caltech.edu | whose bourne no traveler returns"
| -Hamlet, Act III
J.Cernac@johncernac
Its not the so much the ph of the acid but rather if it is either classified as
a strong or weak acid. Strong acids (H2SO4, HNO3, HClO4, HBR, HCl and HI)
disassociate completly where as weaker acids acetic (vinegar) lemon juice may
only disassocaite 1%, therefore the concentration of H is greater in the strong
acid. It is this H that reacts when coming in contact with skin or other
organic material. In acids such as HNO3 and HClO4 you also have to take into
account that these acids are also strong oxidzing agents. The N and Cl have the
potential of making a significant change in oxidation. The same is also true of
bases most hydroxides of Group IA and IIA are considered strong but in there
case it is the concentration of the OH.
jöGeiger Joerg
: We observe that acid has an affinity for glass. We hear tales of
: people getting acid burns or being disinterated with acid, such
: as an old superman series where a criminal tried to use the Statute of
: I am guessing that bases (hydroxides) are much more caustic than acid.
: We know of many ways that people expose themselves to acid without
: harm. People drink lemonade and enjoy it immensely. Can you get Real
: I propose that perhaps acid becomes caustic in glass because the stray
: hydrogen ions are absorbed by the glass, leaving more caustic
: chemicals in solution. -David-
Acids do not have any kind of "affinity" to glass .
But the surface of normal glass ( not quartz glass) may act as
an ion exchanger ( glass is mainly sodium or potassium silicate) .
Glass can be destroyed by hot, concentrated bases (eg. sodium hydroxide)
thus forming sodium polysilicates. But it is also destroyed by hydrogen
fluoride forming SiF4.
Some acids are also strong oxidizing agents (HNO3, HClO4, H2SO4 etc.)
and can readily destroy organic material and metals.
But all these effects are chemical reactions which have nothing
to do with acidity. Non-oxidizing acids ( HCl, H3PO4) do only slight harm
on skin while strong bases cause painful injuries. This is because acids
do only destroy the surface as a crust is readily formed, which protects then
the skin . While bases let the skin swell and thus can reach deeper.
So I hope you understand that "caustic" is not a very useful term.
It just depends which effects of acids or bases you look upon.
- Joerg -
-------------------------------
gei...@vax.rz.uni-wuerzburg.d400.de
------------------------------------------
Department of Clinical Biochemistry & Pathobiochemistry
University of Wuerzburg (FRG)
--------------------------------------------------------
Philip L. Gravel
In article <1994Mar18....@wubios.wustl.edu>, <da...@wubios.wustl.edu>
writes:
> We observe that acid has an affinity for glass.
Not that I am aware of with the notable exception of HF.
> We hear tales of
> people getting acid burns or being disinterated with acid, such
> as an old superman series where a criminal tried to use the Statute of
> Limitations law to avoid prosecution by sealing himself in a concrete
> chamber that could only be breached by the application of an acid.
>
> I am guessing that bases (hydroxides) are much more caustic than acid.
I think you're confusing caustic with corrosive. In a strict chemical
sense, only bases (by definition) are caustic. Both acids and bases can
be corrosive.
> We know of many ways that people expose themselves to acid without
> harm.
There's a difference between strong and weak acids.
> People drink lemonade and enjoy it immensely. Can you get Real
> Lemon on your skin without harm?
Yes. Real Lemon is nothing more than (reconstituted) lemon juice. Citric
acid, the primary acid in lemon juice, is a relatively weak acid.
> People are known to have highly
> acidic stomachs without melting down.
The stomach has a mucous lining that protects it.
> I propose that perhaps acid becomes caustic in glass because the stray
> hydrogen ions are absorbed by the glass, leaving more caustic
> chemicals in solution. -David-
Actually, glass is inert to almost all acids, HF being a notable exception.
Caustics (bases such as sodium hydroxide) can corrode (eat away) glass and
are better stored in plastic (polyethylene or polypropylene) containers.
Phil
-----
Philip L. Gravel Internet: pgr...@amoco.com
Amoco Chemical Company, Chicago, IL Phone: (312)856-3553
----------
These opinions aren't worth the paper they're written on and
certainly don't reflect those of my employer.
Jack Treger
DA>people getting acid burns or being disinterated with acid, such
DA>as an old superman series where a criminal tried to use the Statute of
DA>Limitations law to avoid prosecution by sealing himself in a concrete
DA>chamber that could only be breached by the application of an acid.
DA>I am guessing that bases (hydroxides) are much more caustic than acid.
DA>We know of many ways that people expose themselves to acid without
DA>harm. People drink lemonade and enjoy it immensely. Can you get Real
DA>Lemon on your skin without harm? People are known to have highly
DA>acidic stomachs without melting down.
DA>I propose that perhaps acid becomes caustic in glass because the stray
DA>hydrogen ions are absorbed by the glass, leaving more caustic
DA>chemicals in solution. -David-
Of course!!
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ş SLMR 2.1a ş -