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for hundreds of years
alchemy has captured our imaginations
taking center stage in games in
novels and films it became popular in
the middle ages but it has existed in
one form or another for thousands of
years
and at the heart of it was the quest to
create the philosopher's stone
a waxy red material that alchemists
believed
could turn ordinary metals into gold
unfortunately for them of course there
is no such thing as the philosopher's
stone and this is impossible unless they
are radioactive or in a nuclear reactor
atoms
are stuck forever as the same element
but while on that hopeless quest
alchemists
spent a lot of time studying the
properties of various chemicals and how
they interacted so although we often
talk about alchemy in the same way we
might describe
magic it actually formed the foundation
of modern chemistry and
medicine and it led to some huge
discoveries
before mendeleev put together his draft
of the periodic table in 1869 alchemists
worked mostly off aristotle's
understanding of the elements back from
around 300 bce
aristotle had proposed that all matter
was divided into four elements
water earth fire and air but through
their experimentation
alchemists discovered some of the
official chemical elements we know today
one of those was phosphorus a critical
ingredient in modern matches
fertilizers and explosives phosphorus
was discovered by the german alchemist
hennig brandt in 1669 after a
long smelly day of searching for the
philosopher's stone smelly because
brandt's experiment used
human urine he'd spent about two weeks
boiling more than
four and a half tons of it now it isn't
clear why he was doing this but
alchemists were often experimenting with
various chemicals trying to create new
compounds so like maybe
that was just a normal tuesday forum
either way when it was done
brandt was left with a tar-like
substance which he heated again with
sand and charcoal
he kept the mixture at the highest
temperature he could sustain and after
many hours
a white vapor formed and then condensed
into thick drops that glowed brightly
for hours brandt named the substance
phosphorus from the latin
for light bearing he believed that
phosphorus unique properties would help
him come closer to unlocking the secrets
of the philosopher's stone
i mean it wouldn't but he did figure out
some pretty significant chemistry see
urine contains both the chemical
phosphate and a bunch of organic
molecules when it's heated the oxygen
atoms and the phosphate react with
carbon from the organic material and the
charcoal
and they form carbon monoxide gas the
carbon monoxide escapes and then you're
just left with elemental phosphorus
first as a vapor and then ultimately as
a solid once it drops below 44 degrees
celsius was brent lucky that he didn't
kill himself with the carbon monoxide
that he produced
absolutely but weirdly enough this is
basically the same process used to
produce phosphorus today although
instead of p
we use phosphate ore from the ground so
against all
odds brandt was really onto something
and at first
he actually tried to keep his discovery
a secret however
and this probably wasn't a great plan if
he was trying to keep a secret he sold
the recipe for phosphorus to a fellow
german alchemist that guy let slip to
yet another alchemist named robert boyle
that phosphorus quote
belonged to the body of man that led
boyle to make some educated guesses and
he began to also
experiment with urine discovering the
secret of phosphorus for himself and at
that point
the secret was out for good boyle not
only published the recipe for phosphorus
he also used it to create an
early prototype of phosphorus tipped
matches
next alchemy is also responsible for the
discovery of three
super important chemicals called the
mineral acids
nitric acid sulfuric acid and
hydrochloric acid
all of these are frequent players and
common chemical reactions and can be
found
everywhere from high school chemistry
labs to leading research institutions
and factories and all three were
discovered by alchemists
again as part of their hunt for the
philosopher's stone
this time these acids interested
alchemists because of their unique
properties
for one when mixed with other substances
they helped transform one compound into
another
not like lead into gold but stuff like
turning baking soda into table salt
that seems like a pretty significant
transformation so maybe lead to gold is
possible
also when concentrated and combined with
each other the mineral acids could
create
incredibly corrosive compounds such as
aquaregia
which can dissolve metal since their
main goal was to convert lead into gold
any chemical that interacted with metal
like this was something alchemists were
super fascinated by now some of these
reactions are pretty simple so it's not
surprising that somebody stumbled upon
them like
to make hydrochloric acid alchemists
just heated table salt in a crucible
that broke the salt into compounds
including chlorine gas
and that reacted with water in the air
to make hydrochloric acid but other
processes
seemed a little more complicated or at
least a little more random
like take nitric acid alchemists called
this aquaphortis or strong water because
of its corrosive properties it isn't
clear who
first discovered it but we know its
history begins in the works of persian
alchemists in the 800s
and then later in the works of the
german saint albert the great in the
13th century
and thankfully they did not make it
using urine instead it was prepared by
heating saltpeter
with the seemingly random combination of
alum and copper
sulfate pentahydrate when these
compounds are heated together their
chemical bonds break apart
and new bonds are formed this ultimately
gets you nitrogen dioxide in water which
then combine to form nitric acid today
we figured out how to make this more
efficiently using ammonia but this early
alchemy work really set the stage for
that so even though it's not clear
exactly how
alchemists came up with these ideas we
are grateful they did
today nitric acid arguably plays an even
bigger role in our world than it did
back then
since we use it for the production of
fertilizers plastics dyes and also in
explosives similarly the discovery of
sulfuric acid
also goes quite a ways back it's often
credited to either the persian alchemist
muhammad ibn zechariah al-razi in the
late 800s
or to the islamic writer jabir ibn
haiyan in the 1200s like many of these
stories it's not clear
what they were ultimately up to besides
the whole make the philosopher's stone
bit but in the al-razi story he somehow
found himself roasting iron sulfate with
copper sulfate pentahydrate when these
compounds are heated together
water and sulfur trioxide evaporates
from the mixture
reacting in the air to form sulfuric
acid which can be collected as it
condenses
although back then it was called oil of
vitriol i assume because
it was mean sulfuric acid produced by
this process was functional but
weak it was often mixed with water and
other impurities so again this is not
how we make it today but sulfuric acid
is still
widely used of course in particular it's
a key ingredient in the production of
phosphoric acid
which is a major component of
fertilizers and detergents it's also
used in the iron and steel industry to
remove
rust from metal before it's sold and it
has roles in paper-making petroleum
refining and water purification and
because sulfuric acid is great for
dissolving organic material it's often
used in drain cleaners
so the next time you're unclogging your
bathroom sink thank an alchemist as you
pour it down and you say
oil of vitriol from the basic elements
to
acids alchemists set the stage for a
great deal of modern chemistry but to be
fair
that's not what every alchemist was
interested in some were interested more
in biology
and medicine and their work was no less
groundbreaking one such man was a swiss
alchemist who wrote under the pseudonym
paracelsus
he believed that the principles of
alchemy could be applied to the organs
of the body
basically he thought that the primary
purpose of the body's organs
was to separate the pure from the impure
this was a broader definition of alchemy
than most of his peers might have used
and paracelsus wasn't so much interested
in finding the philosopher's stone as he
was
and just understanding the world and the
rules that governed it which was very
modern of him one of his most
controversial ideas was that our quote
inner alchemist worked to separate
poison from non-poison and while that
definitely
isn't right in exploring the idea
paracelsus came to a conclusion that
still applies today
whether something is poisonous is a
question of dosage
at the time he was researching the
therapeutic properties of several
compounds that his contemporaries
thought were too poisonous to be used in
medicine but he argued that at low doses
poisonous substances could have
important medicinal benefits
conversely large amounts of anything
even
water and oxygen could be poisonous and
he was totally right and people even
today struggle with this idea
that it's okay to have small amounts of
things that would otherwise be poisonous
this was a dramatically new way of
thinking about poison
and it led to a new science toxicology
paracelsus was also responsible for
bringing chemistry into medical
treatments
by using synthetic chemical compounds to
create new drugs
rather than relying only on herbal
remedies still despite all these
contributions
alchemy had a lot of problems as a
science at the time alchemists were
looked at with suspicion particularly by
the church who worried that alchemists
were heretics or
practitioners of witchcraft so to avoid
trouble many kept their findings
secret maybe just to avoid people asking
why did you need
so much urine when they did write notes
they wrote them
in code so that no one else would be
able to make sense of them
including you know modern day historians
trying to piece together the history of
science many were also suspicious of
their peers
and reluctant to share their results
with each other this secrecy meant that
new compounds weren't given standardized
names and were possibly discovered
multiple times by different alchemists
and because there was of course no good
peer review process
alchemists could claim just about
anything they wanted
the only people who could prove them
wrong were other alchemists and because
alchemists didn't share their methods
it often took forever for claims to be
disproven also
there was no established scientific
method so many alchemists investigations
were nothing like the experiments of
scientists today which are based around
testing a hypothesis that said
alchemists weren't just
illusionists or liars either many of
them were serious
about understanding nature and while
some might only have been in it to
discover
eternal life or the ability to create
gold others had the same goals as modern
scientists to understand the rules that
governed the world around them still
as modern scientific thought developed
and more rigorous standards became
commonplace
alchemy eventually faded away and the
chemistry that we know today
emerged but alchemy remains an important
part of the field's history and a
reminder
that science doesn't always need to get
it right on the first
try to be important and useful through
testing and experimentation we can sort
out our missteps and distill them down
into something closer to the truth we
will probably never know everything
about the universe but if we
consistently test
ourselves and the world around us we can
start to uncover
big pieces of it the result might not be
as shiny as gold
but it will be a whole lot more valuable
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you