Carl Wilhelm Scheele was the first to isolate
its gas
but he thought it was oxidized hydrochloric acid,
which he called “dephlogisticated muriatic
acid.”
Thirty-six years later, Humphry Davy
showed it contained no oxygen, and was, in fact,
a new element, which he called “chlorine.”
The meaning of oxygen
Scheele thought his “dephlogisticated
muriatic acid”
was dephlogisticated because it acted as an acid.
Antoine Lavoisier had taught that acids had to
be dephlogisticated,
that is, that oxygen was the principle that made things
acidic.
Pale green
Sodium chlorine, common salt,
as necessary for human life as water.
Chlorine or chloramine as a disinfectant
in our water supplies
at four parts per million, ideally,
except as a shock treatment at forty,
in swimming pools at three, typically,
not to exceed ten, legally,
killing algae, bacteria, viruses,
and creatures in aquariums.
reacting with urine to produce volatile toxins
damaging lungs, hearts, and central nervous systems
although water without a disinfectant
damages more, killing people.
Extremely toxic to all living things,
elemental chlorine gas was the first chemical
weapon
causing coughing and vomiting
at thirty parts per million
and lung damage at sixty parts per million.
Offenses
I don’t think I like it, or the thought of
it,
in this escalating war of invisible agents
both friends and foes offend.
Our defenses are inadequate.
Too much, too many, too often,
too close, too far, too weak, too strong,
too soon, too late, and too unfair.
For an explanation, too contravoluted to repeat here, of why
“dephlogisticated” meant oxygenated, look up
phlogiston theory or see “Combustion.”
It took a long time for chemistry to disengage from alchemy, but
Lavoisier was one of the first to do it.
For an explanation, too contravoluted to repeat here, of why “dephlogisticated” meant oxygenated, look up phlogiston theory or see “Combustion.” It took a long time for chemistry to disengage from alchemy, but Lavoisier was one of the first to do it.
See also in The book of science:
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