chemistry.bigb

= Chemistry
{wiki}

Chemistry is fun. Too hard for precise <physics> (pre <quantum computing>, see also <quantum chemistry>), but not too hard for some maths like <social sciences>.

And it underpins <biology>.

\Video[https://www.youtube.com/watch?v=oSBM2SXlGC]
{title=100 Greatest Discoveries - Chemistry by the Discovery Channel (2005)}
{description=Pretty good within what you can expect from <popular science>. The discovery selection is solid, and he interviews 3 <Nobel Prize> laureates, only one about stuff they invented, so you can see their faces. The short non-precise scenes of epoch are also pleasing. Part of <100 Greatest Discoveries by the Discovery Channel (2004-2005)>.}

= Atom
{parent=Chemistry}
{tag=1926 Nobel Prize in Physics}
{wiki}

= Atomic theory
{synonym}

Theory that atoms exist, i.e. matter is not continuous.

Much before atoms were thought to be "experimentally real", chemists from the 19th century already used "conceptual atoms" as units for the proportions observed in macroscopic chemical reactions, e.g. $2 H_2 + O_2 \leftrightarrow H_{2}O$. The thing is, there was still the possibility that those proportions were made up of something continuous that for some reason could only combine in the given proportions, so the atoms could only be strictly consider calculatory devices pending further evidence.

<Subtle is the Lord by Abraham Pais (1982)> chapter 5 "The reality of molecules" has some good mentions. Notably, physicists generally came to believe in atoms earlier than chemists, because the phenomena they were most interested in, e.g. pressure in the <ideal gas law>, and then <Maxwell-Boltzmann statistics> just scream atoms more loudly than chemical reactions, as they saw that these phenomena could be explained to some degree by traditional mechanics of little balls.

Confusion around the probabilistic nature of the <second law of thermodynamics> was also used as a physical counterargument by some. Pais mentions that <Wilhelm Ostwald> notably argued that the <time reversibility of classical mechanics> + the second law being a fundamental law of physics (and not just probabilistic, which is the correct hypothesis as we now understand) must imply that atoms are not classic billiard balls, otherwise the second law could be broken.

Pais also mentions that a big "chemical" breakthrough was <isomers suggest that atoms exist>.

Very direct evidence evidence:
* <Brownian motion> mathematical analysis in 1908. Brownian motion just makes it too clear that liquids cannot be continuous... if they were, there would obviously be no <Brownian motion>, full stop.
* <X-ray crystallography>: it \i[sees] crystal latices
* <scanning tunnelling microscope>: it \i[sees] individual atoms for Christ's sake, what else do you want?

  \Image[https://upload.wikimedia.org/wikipedia/en/3/37/A_Boy_and_His_Atom_%28still%29.jpg]
  {title=Still from https://en.wikipedia.org/wiki/A_Boy_and_His_Atom[A boy and his atom] by <IBM>}
  {source=https://en.wikipedia.org/wiki/File:A_Boy_and_His_Atom_(still).jpg}

Less direct evidence:
* 1874 <Isomers suggest that atoms exist>
* <kinetic theory of gases> seems to explain certain phenomena really well

<Subtle is the Lord by Abraham Pais (1982)> page 40 mentions several methods that <Einstein> used to "prove" that atoms were real. Perhaps the greatest argument of all is that several unrelated methods give the same estimates of atom size/mass:
* from 1905:
  * in light quantum paper
  * enabled by experimental work of https://en.wikipedia.org/wiki/Wilhelm_Pfeffer[Wilhelm Pfeffer] on producing rigid membranes
    * sugar molecules in water
    * <Brownian motion>: <investigations on the theory of the Brownian movement by Einstein (1905)>
* 1911: blueness of the sky and critical opalescence

= History of the atomic theory
{parent=Atom}

= Les Atomes by Jean Perrin (1913)
{parent=History of the atomic theory}
{tag=Work by Jean Perrin}

<Subtle is the Lord by Abraham Pais (1982)> mentions that this has a good summary of the <atomic theory evidence> that was present at the time, and which had become basically indisputable at or soon after that date.

On <Wikimedia Commons> since it is now <public domain> in most countries: https://commons.wikimedia.org/w/index.php?title=File:Perrin,_Jean_-_Les_Atomes,_F%C3%A9lix_Alcan,_1913.djvu

An <English (language)> translation from 1916 by <English> chemist https://en.wikipedia.org/wiki/Dalziel_Hammick[Dalziel Llewellyn Hammick] on the <Internet Archive>, also on the public domain: https://archive.org/details/atoms00hammgoog

= Atomic theory evidence
{parent=Atom}

= Isomers suggest that atoms exist
{parent=Atomic theory evidence}
{title2=1874}
{wiki}

<Subtle is the Lord by Abraham Pais (1982)> page 85:
> However, it became increasingly difficult in chemical circles to deny the reality of molecules after 1874, the year in which Jacobus Henricus van't Hoff and Joseph Achille Le Bel independently explained the <isomerism> of certain organic substances in terms of <stereochemical> properties of carbon compounds.
so it is quite cool to see that <organic chemistry> is one of the things that pushed atomic theory forward. Because when you start to observe that <isomers> has different characteristics, despite identical proportions of atoms, this is really hard to explain without talking about the relative positions of the atoms within molecules!

TODO: is there anything even more precise that points to atoms in stereoisomers besides just the "two isomers with different properties" thing?

= Brownian motion
{c}
{parent=Atomic theory evidence}
{title2=1785 or 1827}
{wiki}

Small microscopic visible particles move randomly around in water.

If water were continuous, this shouldn't happen. Therefore this serves as one important evidence of <atomic theory>.

The amount it moves also quantitatively matches with the expected properties of water and the floating particles, was was settled in 1905 by <Einstein> at: <investigations on the theory of the Brownian movement by Einstein (1905)>.

This suggestion that Brownian motion comes from the movement of atoms had been made much before Einstein however, and passed tortuous discussions. <Subtle is the Lord by Abraham Pais (1982)> page 93 explains it well. There had already been infinite discussion on possible causes of those movements besides <atomic theory>, and many ideas were rejected as incompatible with observations:
> Further investigations eliminated such causes as temperature gradients, mechanical disturbances, capillary actions, irradiation of the liquid (as long as the resulting temperature increase can be neglected), and the presence of convection currents within the liquid.
The first suggestions of atomic theory were from the 1860s.

Tiny uniform plastic beads called "microbeads" are the preferred 2019 modern method of doing this: https://en.wikipedia.org/wiki/Microbead

Original well known observation in 1827 by Brown, with further experiments and interpretation in 1908 by <Jean Baptiste Perrin>. Possible precursor observation in 1785 by https://en.wikipedia.org/wiki/Jan_Ingenhousz[Jan Ingenhousz], not sure why he wasn't credited better.

\Video[http://youtube.com/watch?v=UUSL0NqcY6k]
{title=Observing Brownian motion of micro beads by Forrest Charnock (2016)}

= Ion
{parent=Atom}
{wiki}

= Mole
{disambiguate=unit}
{parent=Atom}
{wiki}

= Mole
{synonym}

= Model of the atom
{parent=Atom}

= Bohr model
{c}
{parent=Model of the atom}
{title2=1913}
{wiki}

Was the first model to explain the <Balmer series>, notably linking atomic spectra to the <Planck constant> and therefore to other initial <quantum mechanical> observations.

This was one of the first major models that just said:
> I give up, I can't tie this to <classical physics> in any way, let's just roll with it, OK?

It still treats <electrons> as little points spinning around the nucleus, but it makes the non-<classical physics>[classical] postulate that only certain angular momentums (and therefore energies) are allowed.

Bibliography:
* <Inward Bound by Abraham Pais (1988)> Chapter 9.e Atomic structure and spectral lines - Niels Bohr
* <The Quantum Story by Jim Baggott (2011)> Chapter 3 A Little Bit of Reality

= Quantum jump
{parent=Bohr model}
{wiki}

Bagic jump between orbitals in the <Bohr model>. Analogous to the later <wave function collapse> in the <Schrödinger equation>.

<Causality and quantum jumps are incompatible>.

= Bohr-Sommerfeld model
{c}
{parent=Bohr model}
{title2=1916}
{wiki}

Refinement of the <Bohr model> that starts to take quantum <angular momentum> into account in order to explain missing lines that would have been otherwise observed TODO specific example of such line.

They are not observe because they would violate the conservation of angular momentum.

Introduces the <azimuthal quantum number> and <magnetic quantum number>.

TODO confirm year and paper, Wikipedia points to: https://zenodo.org/record/1424309#.yotqe3xmjhe[]

= Analytical chemistry
{parent=Chemistry}
{wiki}

= Gas chromatography
{parent=Analytical chemistry}
{title2=GC}
{wiki}

This technique is crazy! It allows to both:
* separate gaseous mixtures
* identify gaseous compounds
You actually see discrete peaks at different minute counts on the other end.

It is based on how much the gas interacts with the column.

Detection is usually done burning the sample to ionize it when it comes out, and then you measure the current produced.

The procedure remind you a bit of <gel electrophoresis>, except that it is in gaseous phase.

\Video[https://www.youtube.com/watch?v=UycPljfrnWo]
{title=<Gas chromatography> by Quick Biochemistry Basics (2019)}

\Video[https://www.youtube.com/watch?v=A8rX7zxyu_c]
{title=How I invented the electron capture detector interview with James Lovelock by Web of Stories (2001)}
{description=He mentions how scientists had to make their own tools during the 40s/60s. Then how <gas chromatography> was invented at the <National Institute for Medical Research> and gained a <Nobel Prize>. Lovelock came in improving the detection part of things.}

= Gas chromatography etymology
{parent=Gas chromatography}

= Why is gas chromatography called "chromatography"?
{synonym}
{title2}

The name makes absolutely no sense in modern terms, as nor colors nor light are used directly in the measurements. It is purely historical.

https://www.chromatographytoday.com/news/gc-mdgc/32/breaking-news/why-is-chromatography-called-chromatography/31178

= Analyte
{parent=Analytical chemistry}
{wiki}

= Analytical chemistry method
{parent=Analytical chemistry}

= Ion selective electrode
{parent=Analytical chemistry method}
{title2}
{wiki}

An <ion selective electrode> is tool used in  <analytical chemistry> used to determine the concentration of a given <ion> in a solution.

The method can determine the concentration of one ion even if there are multiple different types of <ion> in the solution, although in some cases this can alter the results. This is done with the help of a selective membrane that only allows certain ions through.

One cool example application mentioned on <LibreTexts>https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Physical_Methods_in_Chemistry_and_Nano_Science_(Barron)/01%3A_Elemental_Analysis/1.07%3A_Ion_Selective_Electrode_Analysis{ref} is the measurement of <fluorine> concentration in water. They explain that <fluorine> is added to the drinking water supply in some countries to help protect people's teeth, and so you want to be able to measure as part of quality control to make sure it is being added in correct the quantities.

The method requires calibrating with calibrating solutions which takes one hour, but once you are calibrated you just stick the sensor into the <analyte> and get readings in a minute without any expendables. The membrane seems to be a bit fragile which requires care, but overall it looks like a convenient method.

\Image[https://upload.wikimedia.org/wikipedia/commons/9/95/General_ISE_Set-Up.png]
{title=<Ion selective electrode> schematic}
{height=600}

\Image[https://web.archive.org/web/20220605032719im_/https://files.mtstatic.com/site_4334/142875/0?Expires=1654403194&Signature=aAPjJy6lmj0OVoTs6TFibKDDW1XlYFMdZp9qCdNChcca6NCOaHHQqFu1oH9gzt6Dwe2YZMW1WdaPkvN8kAoW29qoXQ-ExXs9XeIA0AhtuQSO3GvNXaiVISse2zEWtHB2wYz5KRggWJ6qHk34z8Jti8w5V0Qwqg6hK6RHt5AmGkw_&Key-Pair-Id=APKAJ5Y6AV4GI7A555NA]
{title=Sample calibration curve for an <ion selective electrode>}
{description=The curve is simple and log linear, so once you have that it is easy to fit new measurements to the curve.}
{height=600}
{source=https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Physical_Methods_in_Chemistry_and_Nano_Science_(Barron)/01%3A_Elemental_Analysis/1.07%3A_Ion_Selective_Electrode_Analysis}

\Video[https://www.youtube.com/watch?v=bGO_GvpVwVU]
{title=General Principles of Ion Selective Electrodes by Jacob Stewart}

\Video[https://www.youtube.com/watch?v=5NREQwnaGcE]
{title=<Ion selective electrodes> Tech Tips by Vernier}
{description=
The plump <Asian American> lady with a <PhD> explains how to use the thing.

It seems like a proprietary training video given with the product that this Peruvian university decided to upload to <YouTube>. Heroes.
}

\Video[https://www.youtube.com/watch?v=NHByG4g5-RE]
{title=Using an Ion Selective Electrode by <University of Alberta>}

Bibliography:
* https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Physical_Methods_in_Chemistry_and_Nano_Science_(Barron)/01%3A_Elemental_Analysis/1.07%3A_Ion_Selective_Electrode_Analysis

= Separation process
{parent=Analytical chemistry method}
{wiki}

= Chemist
{parent=Chemistry}
{wiki}

= Alfred Nobel
{c}
{parent=Chemist}
{wiki}

= Joseph Priestley
{c}
{parent=Chemist}
{tag=Notable private tutor}
{title2=1733-1804}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/2/20/Joseph_Priestley.jpeg]
{title=Joseph Priestley in 1801}

= Johann Joseph Loschmidt
{c}
{parent=Chemist}
{wiki}

= Linus Pauling
{c}
{parent=Chemist}
{tag=1954 Nobel Prize in Chemistry}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/5/53/Linus_Pauling_in_the_1940s.jpg]
{title=<Linus Pauling> in the 1940s}
{height=600}

\Video[https://www.youtube.com/watch?v=xYVkJwVo__A]
{title=Why Linus Pauling was the Smartest Quack in History by MQTate}

\Video[https://www.youtube.com/watch?v=YBUGRh6WFyk]
{title=The Sad Decline of America's Greatest Chemist by MQTate}

= Wilhelm Ostwald
{c}
{parent=Chemist}
{tag=1908 Nobel Prize in Chemistry}
{wiki}

= Ostwald
{c}
{synonym}

= Chemical element
{parent=Chemistry}
{wiki}

= Abundance of the chemical elements
{parent=Chemical element}
{wiki}

= Abundance of the chemical elements on Earth
{parent=Abundance of the chemical elements}
{tag=Earth}

= Primordial nuclide
{parent=Abundance of the chemical elements on Earth}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/0/09/Elemental_abundances.svg]
{height=700}

= Discovery of chemical elements
{parent=Chemical element}
{wiki}

= Discovery of chemical elements bibliography
{parent=Discovery of chemical elements}

* https://www.periodictable.one/history/timeline

= Discovery Of The Elements by Mary Elvira Weeks
{parent=Discovery of chemical elements bibliography}

6th edition (1956) on the <Internet Archive>: https://archive.org/details/discoveryoftheel002045mbp

= Category of chemical element
{parent=Chemical element}

= Rare-earth element
{parent=Category of chemical element}
{wiki}

\Video[https://www.youtube.com/watch?v=4LiYdbNqkwg]
{title=The Secrets of the Super Elements}
{description=2019, by the <BBC>. Official page: https://www.bbc.co.uk/programmes/b08rv9r6[].}

= List of chemical elements
{parent=Chemical element}

= Hydrogen
{parent=List of chemical elements}
{title2=H}
{title2=1}
{wiki}

= Isotope of hydrogen
{parent=Hydrogen}
{wiki=Isotopes of hydrogen}

= Protium
{parent=Isotope of hydrogen}
{title2=\sup[1]H}
{title2=stable}
{title2=99.98%}
{wiki}

= Deuterium
{parent=Isotope of hydrogen}
{title2=\sup[2]H}
{title2=stable}
{title2=0.02%}
{wiki}

Applications:
* because it has an even number of <nucleons> it is transparent to <NMR>, and therefore is useful in solvents for <NMR spectroscopy>

= Heavy water
{parent=Deuterium}
{tag=Water}
{wiki}

<Cody'sLab> had a nice 5 video series on making it at home! But the <United States Government> asked him to take it down as suggested at <video What's Been Going On With Cody'sLab? by Cody'sLab (2019)> at https://youtu.be/x1mv0vwb08Y?t=84.

Here's a copy online as of 2020: https://www.youtube.com/watch?v=bCXB6BdMh9Y

= Semiheavy water
{parent=Heavy water}
{wiki}

= Girdler sulfide process
{c}
{parent=Heavy water}
{wiki}

= Tritium
{parent=Isotope of hydrogen}
{title2=\sup[3]H}
{title2=12 y}
{wiki}

Used in:
* <boosted fission weapon>
* <magnetic confinement fusion>

= Hydrogen compound
{parent=Hydrogen}
{tag=Chemical compound}

= Water
{parent=Hydrogen compound}
{tag=Chemical substance}
{tag=Oxygen compound}
{wiki}

"Water" is the name for both:
* the <chemical compound> with <#chemical formula> H\sub[2]O
* the <liquid phase> of the <chemical substance> composed of the above <chemical compound>

\Image[https://upload.wikimedia.org/wikipedia/commons/8/8a/2006-02-13_Drop_before_impact.jpg]
{title=<Water> in a glass}

\Image[https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Water-3D-balls-A.png/800px-Water-3D-balls-A.png]
{title=<Ball-and-stick model> of a <water molecule>}
{disambiguate=water}

\Image[https://upload.wikimedia.org/wikipedia/commons/3/33/Phase_diagram_of_water_simplified.svg]
{title=Simplified <phase diagram> of <water>}
{description=Note the <triple point> and <critical point (thermodynamics)> visible. <Phase diagrams> are so cool!}
{height=600}

\Image[https://upload.wikimedia.org/wikipedia/commons/0/08/Phase_diagram_of_water.svg]
{title=<Phase diagram> of <water>}
{description=Note all the obscure <phases of ice>.}
{height=600}

= Water molecule
{parent=Water}
{title2=$\text{H}_2\text{O}$}

\Image[https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Water-3D-balls-A.png/800px-Water-3D-balls-A.png]
{title=<Ball-and-stick model> of a <water molecule>}

= Phase of water
{parent=Water}
{wiki}

= Ice
{parent=Phase of water}
{wiki}

Ice is the name of one of the <solid phases> of <water>.

In informal contexts, it usually refers to the <phase of ice> observed in <#atmospheric pressure>, <Ice Ih>.

= Phase of ice
{parent=Ice}
{wiki=Phases of ice}

= Phases of ice
{synonym}

= Ice I\sub[h]
{parent=Phase of ice}

= Snow
{parent=Ice}
{wiki}

= Helium
{parent=List of chemical elements}
{tag=Noble gas}
{title2=He}
{title2=2}
{wiki}

= Helium-3
{parent=Helium}
{wiki}

= Helium-4
{parent=Helium}
{wiki}

= Liquid helium
{parent=Helium}
{title2=4.2 K}
{wiki}

= Helium I
{synonym}
{title2}

4 K. Enough for to make "low temperature <superconductors>" like regular metals superconducting, e.g. the <superconducting temperature of aluminum> if 1.2 K.

Contrast with <liquid nitrogen>, which is much cheaper but only goes to 77K.

= Superfluid helium
{parent=Liquid helium}

= Superfluid helium-3
{parent=Superfluid helium}
{tag=1996 Nobel Prize in Physics}
{title2=observed 1972}
{wiki}

Surprisingly, it can also become a <superfluid> even though each atom is a <fermion>! This is because of <Cooper pair> formation, just like in <superconductors>, but the transition happens at lower temperatures than <superfluid helium-4>, which is a <boson>.

https://aps.org/publications/apsnews/202110/history.cfm[]: October 1972: Publication of Discovery of Superfluid Helium-3 contains comments on the seminal paper and a graph which we must steal.

= Superfluid helium-4
{parent=Superfluid helium}
{wiki}

= Helium II
{synonym}
{title2}

Also sometimes called <helium II>, in contrast to <helium I>, which is the non-<superfluid> <liquid helium> phase.

\Video[https://www.youtube.com/watch?v=unUNQNmuvUQ]
{title=<Superfluid helium> Resonance Experiment by <Dietterich Labs> (2019)}

= Boron
{parent=List of chemical elements}
{title2=B}
{title2=5}
{wiki}

= Carbon
{parent=List of chemical elements}
{title2=C}
{title2=6}
{wiki}

= Carbon isotope
{parent=Carbon}

= Carbon-12
{parent=Carbon isotope}
{title2=stable}
{title2=99%}
{wiki}

= Carbon-13
{parent=Carbon isotope}
{title2=stable}
{title2=1%}
{wiki}

= Carbon-14
{parent=Carbon isotope}
{title2=5 ky}
{wiki}

= Radiocarbon dating
{parent=Carbon-14}
{wiki}

= Before Present
{c}
{parent=Radiocarbon dating}
{wiki}

= Carbon compound
{parent=Carbon}
{wiki}

= Allotrope of carbon
{parent=Carbon compound}
{tag=Allotrope of carbon}
{wiki=Allotropes_of_carbon}

= Allotropes of carbon
{synonym}

= Diamond
{parent=Allotrope of carbon}
{wiki}

= Fullerene
{parent=Allotrope of carbon}
{wiki}

\Video[https://www.youtube.com/watch?v=ljF5QhD5hnI]
{title=Buckyballs (C60) by <Periodic Videos> (2010)}
{description=
Actually shows them in a lab!
* https://youtu.be/ljF5QhD5hnI?t=167 has a photo of the first effective production method, which passes a large current between two carbon rods
* https://youtu.be/ljF5QhD5hnI?t=245 and forward cuts (their editing is very annoying) shows how fullerene dissolves in an organic solvent TODO name, sounds like thodium? and produces a violet solution, while <graphite> doesn't. A https://en.wikipedia.org/wiki/Ultrasonic_cleaning[Ultrasonic bath] is needed for the solution to form however.
* https://youtu.be/ljF5QhD5hnI?t=501 fullerene is not a good lubricant despite being a little ball, because it is reactive and polymerises under pressure
}

= Endohedral fullerene
{parent=Fullerene}
{wiki}

\Video[https://www.youtube.com/watch?v=fFESP1Se1To]
{title=Endohedral Fullerenes by Dom Burges (2016)}

= Graphite
{parent=Allotrope of carbon}
{wiki}

The layered one.

= Nuclear graphite
{parent=Graphite}
{tag=Neutron moderator}
{wiki}

= Graphene
{parent=Graphite}
{wiki}

A single layer of <graphite>.

= Carbonate
{parent=Carbon compound}
{title2=$CO_3^{2-}$}
{wiki}

= Calcium carbonate
{parent=Carbonate}
{title2=$CaCO_3$}
{wiki}

= Calcium carbonate polymorph
{parent=Calcium carbonate}

= Calcite
{parent=Calcium carbonate polymorph}
{wiki}

= Aragonite
{parent=Calcium carbonate polymorph}
{title2=1797}
{wiki}

= Vaterite
{parent=Calcium carbonate polymorph}
{wiki}

= Nitrogen
{parent=List of chemical elements}
{title2=N}
{title2=7}
{wiki}

= Liquid nitrogen
{parent=Nitrogen}
{wiki}

77K. Low enough for "high temperature <superconductors>" such as <yttrium barium copper oxide>, but for "low temperature superconductors", you need to go much lower, typically with <liquid helium>, which is likely much more expensive. TODO by how much?

\Video[https://www.youtube.com/watch?v=PEgm5NFXlFM]
{title=Where Do You Get Liquid Nitrogen? by The King of Random (2016)}
{description=He just goes to a medical gases shop in a local <industrial> estate and buys 20L for 95 dollars and brings it back on his own <Dewar> marked 35LD.}

\Video[https://www.youtube.com/watch?v=dCXkaQa53QQ]
{title=Making Liquid Nitrogen From Scratch! by <Veritasium> (2019)}
{description="From scratch" is perhaps a bit <clickbaity>, but I'll take it.}

= Nitrogen compound
{parent=Nitrogen}

= Ammonium
{parent=Nitrogen compound}
{wiki}

= Oxygen
{parent=List of chemical elements}
{title2=O}
{title2=8}
{wiki}

= Oxygen compound
{parent=Oxygen}
{tag=Chemical compound}

= Quartz
{parent=Oxygen compound}
{title2=$SiO_2$}
{wiki}

<Piezoelectric>, and notably used in <quartz clock>.

= Fluorine
{parent=List of chemical elements}
{title2=F}
{title2=9}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/2/2c/Fluoro_liquido_a_-196%C2%B0C_1.jpg]
{title=Liquid $F_2$}
{description=The boiling temperature is 85.03 K, so the liquid in this photo is very cold.}

= Fluorine compound
{parent=Fluorine}

= Neon
{parent=List of chemical elements}
{tag=Noble gas}
{title2=Ne}
{title2=10}
{wiki}

= Sodium
{parent=List of chemical elements}
{title2=Na}
{title2=11}
{wiki}

= Sodium chloride
{parent=Sodium}
{title2=NaCl}
{wiki}

= Aluminium
{parent=List of chemical elements}
{title2=Al}
{title2=13}
{wiki}

= Superconducting temperature of aluminum
{parent=Aluminium}
{title2=1.2 kelvin}

= Silicon
{parent=List of chemical elements}
{title2=Si}
{title2=14}
{wiki}

= Phosphorus
{parent=List of chemical elements}
{title2=P}
{title2=15}
{title2=3s2 3d3}
{wiki}

= Why phosphorus has multiple valencies?
{parent=Phosphorus}

https://www.quora.com/Why-does-phosphorous-have-a-valency-of-3-and-5

= Phosphate
{parent=Phosphorus}
{title2=$PO_4^{3-}$}
{wiki}

= Sulfur
{parent=List of chemical elements}
{title2=S}
{title2=16}
{wiki}

= Sulfur compound
{parent=Sulfur}

= Sulfur hydrade
{parent=Sulfur compound}
{title2=$H_2O$}
{wiki}

\Video[https://www.youtube.com/watch?v=GRBTQcrObdk]
{title=Danger $H_2S$ by Bayway Refinery}
{description=
TODO year.
* https://youtu.be/GRBTQcrObdk?t=462 scientist exposes a <rat> to the gas, watches the rat faint, and then revives the rat with manual resuscitation. OMG.
}

= Argon
{parent=List of chemical elements}
{tag=Noble gas}
{title2=Ar}
{title2=18}
{wiki}

= Argon is abundant on Earth's atmosphere because it comes from the decay of Potassium-40
{parent=Argon}

And notably, it is almost all <Argon-40>, which is stable, but not the most common one to come from natural <#nucleosynthesis>.

= K-Ar dating
{c}
{parent=Argon is abundant on Earth's atmosphere because it comes from the decay of Potassium-40}
{title2=dates rock crystalization time}
{wiki=K-Ar dating}

= Argon isotope
{parent=Argon}
{wiki=Isotopes_of_argon}

= Argon-40
{parent=Argon isotope}

= Potassium
{parent=List of chemical elements}
{title2=K}
{title2=19}
{title2=$4s^{1}$}
{wiki}

= Calcium
{parent=List of chemical elements}
{title2=Ca}
{title2=20}
{title2=$4s^{2}$}
{wiki}

= Titanium
{parent=List of chemical elements}
{title2=Ti}
{title2=22}
{wiki}

= Titanium compound
{parent=Titanium}

= Niobium-Titanium
{parent=Titanium compound}
{tag=Niobium compound}

= Nb-Ti
{synonym}
{title2}

= Chromium
{parent=List of chemical elements}
{title2=Cr}
{title2=24}
{wiki}

= Iron
{parent=List of chemical elements}
{title2=Fe}
{title2=26}
{wiki}

= Fe-C
{parent=Iron}
{tag=Alloy}

An alloy of <iron> and <carbon>. Because such allys have had such incredible historical importance due to their different properties, different <phases> of <Fe-C> have well known names such as <steel>

\Image[https://upload.wikimedia.org/wikipedia/commons/8/8a/Iron_carbon_phase_diagram.svg]
{title=<Temperature> vs <Carbon>% <phase diagram> of <Fe-C>}

= Steel
{parent=Iron}
{title2=Fe-C}
{wiki}

A <phase> of <Fe-C> characterized by the low ammount of <carbon>.

\Image[https://upload.wikimedia.org/wikipedia/commons/8/8a/Iron_carbon_phase_diagram.svg]

= Cobalt
{parent=List of chemical elements}
{title2=Co}
{title2=27}
{wiki}

= Cobalt isomer
{parent=Cobalt}

= Cobalt-60
{parent=Cobalt isomer}
{wiki}

= Copper
{parent=List of chemical elements}
{title2=Cu}
{title2=29}
{wiki}

= Copper compound
{parent=Copper}

= Gallium
{parent=List of chemical elements}
{title2=Ga}
{title2=31}
{wiki}

= Gallium compound
{parent=Gallium}

= Gallium arsenide
{parent=Gallium compound}
{tag=III-V semiconductor}
{tag=Arsenide compound}
{wiki}

This is apparently the most important <III-V semiconductor>, it seems to actually have some applications, see also: <gallium arsenide vs silicon>.

= Gallium arsenide vs silicon
{parent=Gallium arsenide}

Trying to use <gallium arsenide> was <Seymour Cray>'s fatal last flaw as mentioned at <The Supermen: The Story of Seymour Cray by Charles J. Murray (1997)>.

https://en.wikipedia.org/wiki/Gallium_arsenide#Comparison_with_silicon_for_electronics

<The Supermen: The Story of Seymour Cray by Charles J. Murray (1997)> page 4 mentions:
> Cray wanted his new machine to employ circuits made from a material called gallium arsenide. Gallium arsenide had achieved limited success, particularly in satellite communications and military electronics. But no one had succeeded with it in anything so complicated as a computer. In the computer industry, engineers had developed a saying: "Gallium arsenide is the technology of the future," they would say. "And it always will be."

= GaAs
{c}
{synonym}
{title2}

= Germanium
{parent=List of chemical elements}
{title2=Ge}
{title2=32}
{wiki}

= Arsenide
{parent=List of chemical elements}
{title2=As}
{title2=33}
{wiki}

= Arsenide compound
{parent=Arsenide}

= Selenium
{parent=List of chemical elements}
{title2=Se}
{title2=34}
{wiki}

= Bromine
{parent=List of chemical elements}
{title2=Br}
{title2=35}
{title2=4s2 4p5}
{wiki}

= Bromide
{parent=Bromine}
{title2=$Br^-$}
{wiki}

= Organic bromide compound
{parent=Bromide}
{tag=Organic compound}

= Ethidium bromide
{parent=Organic bromide compound}
{wiki}

= Niobium
{parent=List of chemical elements}
{title2=Nb}
{title2=41}
{wiki}

= Niobium compound
{parent=Niobium}

= Niobium-tin
{parent=Niobium}
{tag=Tin compound}
{wiki}

= $Nb_3Sn$
{synonym}
{title2}

= Nb-Sn
{synonym}
{title2}

Second most important superconducting material: <applications of superconductivity>.

= Silver
{parent=List of chemical elements}
{title2=Ag}
{title2=47}
{title2=4d10 5s1}
{wiki}

= Cadmium
{parent=List of chemical elements}
{title2=Ca}
{title2=48}
{wiki}

= Tin
{parent=List of chemical elements}
{title2=Sn}
{title2=50}
{title2=Stannum}
{wiki}

= Tin compound
{parent=Tin}

= Caesium
{parent=List of chemical elements}
{title2=Cs}
{title2=55}
{title2=$6s^1$}
{wiki}

= Cesium
{synonym}

= Caesium-133
{parent=Caesium}
{title2=stable}
{wiki}

Stable <isotope>.

= Caesium-137
{parent=Caesium}
{title2=radioactive}
{wiki}

Highly <radioactive> <isotope> of <caesium>  with <half-life> of 30.17 <year>[y]. Produced from the <nuclear fission> of <uranium>, TODO exact reaction, not found in nature.

The <fucked> thing about this byproduct is that it is in the same chemical family as <sodium>, and therefore forms a salt that looks like regular <sodium chloride>[table salt], and dissolves in water and therefore easily enters your body and sticks to things.

Another problem is that its <half-life> is long enough that it doesn't lose radioactivity very quickly compared to the life of a human person, although it is short enough to make it highly toxic, making it a terrible pollutant when released.

This is why for example in the <goiânia accident> a girl ended up ingesting Caesium-137 after eating an egg after touching the Caesium with her hands.

\Image[https://upload.wikimedia.org/wikipedia/commons/3/3e/Cs-137-decay.svg]
{title=<caesium-137> decay scheme}

= Goiânia accident
{parent=Caesium-137}
{title2=1987}
{wiki}

\Video[https://www.youtube.com/watch?v=-k3NJXGSIIA]
{title=One handful contaminated a city by Kyle Hill (2021)}

= Barium
{parent=List of chemical elements}
{title2=Ba}
{title2=56}
{title2=$6s^2$}
{wiki}

= Barium compound
{parent=Barium}

= Ytterbium
{parent=List of chemical elements}
{title2=Yb}
{title2=60}
{title2=$4d^1$}
{wiki}

Not "Yt" because that is already "Yttrium". God.

= Gold
{parent=List of chemical elements}
{title2=Au}
{title2=79}
{wiki}

= Gold leaf
{parent=Gold}

\Video[https://youtu.be/RBd67qQy96k?t=233]
{title=Hands: A Dublin Bookbinder}
{description=Some awesome <gold leaf> action!}

= Lead
{parent=List of chemical elements}
{title2=Pb}
{title2=82}
{wiki}

= Bismuth
{parent=List of chemical elements}
{title2=Bi}
{title2=83}
{wiki}

= Bismuth compound
{parent=Bismuth}
{tag=Chemical compound}

= Polonium
{parent=List of chemical elements}
{title2=Po}
{title2=84}
{title2=July 1998}
{wiki}

Discovered by <Marie Curie>, published July 1999.

= Polonium isotope
{parent=Polonium}

There are no stable isotopes.

= Polonium-208
{parent=Polonium isotope}

= Polonium-209
{parent=Polonium isotope}

= Polonium-210
{parent=Polonium isotope}
{tag=Alpha emitter}
{title2=140d}
{wiki}

The only isotope found on <Earth> because it occurs as part of the <uranium 238 decay chain>, i.e., it is not a <primordial nuclide>.

Interestingly it is a bit less stable than other <isotopes>L such as <Polonium-208> (3 y) and <Polonium-209> (124 y), but those aren't in any Earthly radioactive chain so they don't show up on Earth.

= Radium
{parent=List of chemical elements}
{title2=Ra}
{title2=88}
{title2=December 1989}
{wiki}

Discovered by <Marie Curie> when she noticed that there was some yet unknown more radioactive element in their raw samples, after <uranium> and <polonium>, which she published 6 months prior, had already been separated. Published on December 1989 as: <Sur une nouvelle substance fortement radio-active, contenue dans la pechblende>{full}.

The <uranium 238 decay chain> is the main source of naturally occurring <radium>.

\Video[https://www.youtube.com/watch?v=wAZX8sWSCqs]
{title=The epic story of radium by Institut de Radioprotection et de Sûreté Nucléaire (2013)}

= Radium Girls
{parent=Radium}
{wiki}

= Thorium
{parent=List of chemical elements}
{title2=Th}
{title2=90}
{wiki}

= Thorium fuel cycle
{parent=Thorium}
{wiki}

= Thorium isotope
{parent=Thorium}
{wiki=Isotopes of thorium}

= Thorium-229
{parent=Thorium isotope}
{title2=trace}
{title2=8 ky}
{wiki}

This <isomer> has an interest for <atomic clocks> due to an exceptionally low energy <nuclear isomer> transition: https://www.quantamagazine.org/the-first-nuclear-clock-will-test-if-fundamental-constants-change-20240904/

= Thorium-232
{parent=Thorium isotope}
{title2=99.98%}
{title2=14 Gy}
{wiki}

= Thorium-232 decay chain
{parent=Thorium-232}
{tag=Decay chain}

\Image[https://upload.wikimedia.org/wikipedia/commons/2/25/Decay_Chain_Thorium.svg]

= Uranium
{parent=List of chemical elements}
{title2=U}
{title2=92}
{wiki}

= Uranium vs Plutonium
{parent=Uranium}
{tag=Plutonium}

\Video[https://www.youtube.com/watch?v=dgBDvnqMkT4]
{title=The <RaLa Experiment> by <#Our Own Devices>}
{description=Has some good mentions of <Uranium vs Plutonium> in <nuclear weapon> design.}

Bibliography:
* Open Q&As:
  * https://www.quora.com/What-is-the-difference-between-plutonium-and-uranium
    * <Uranium vs plutonium Quora answer by Ciro Santilli>{full}
  * https://www.quora.com/How-many-times-stronger-is-plutonium-than-uranium
    * https://www.quora.com/How-many-times-stronger-is-plutonium-than-uranium/answer/Ciro-Santilli answer by <Ciro Santilli>
* Closed Q&As:
  * https://www.reddit.com/r/explainlikeimfive/comments/15421mk/eli5_why_do_we_use_uranium_and_plutonium_for/ closed
  * https://www.reddit.com/r/explainlikeimfive/comments/1idbux/eli5_whats_the_difference_between_uranium_and/

= Weapon grade Plutonium is cheaper than weapon grade Uranium
{parent=Uranium vs Plutonium}

Because you can generate <plutonium-239> from <uranium-238> in a <breeder reactor>, and then separate the <plutonium-239> from the <Uranium> simply by using <chemistry> methods because you've created an element with different valence electrons.

Isn't it somewhat funny that it is easier to purify a synthetic element than a naturally occurring one?

= Uranium vs plutonium Quora answer by Ciro Santilli
{parent=Uranium vs Plutonium}
{tag=articles}
{tag=Quora}

https://www.quora.com/What-is-the-difference-between-plutonium-and-uranium/answer/Ciro-Santilli

= Uranium compound
{parent=Uranium}

= Uranium oxide
{parent=Uranium compound}
{wiki}

= Uranium dioxide
{parent=Uranium oxide}
{title2=UO\sub[2]}
{wiki}

= Uranium hexafluoride
{parent=Uranium compound}
{tag=Fluorine compound}
{title2=UF\sub[6]}
{title2=Hex}
{wiki}

This is an important man-made <uranium compound> as it is used in <uranium enrichment>.

The main reason for this is that <fluorine> only has one stable <isotope>, which allows you to pick up weight differences in <uranium isotopes> in isolation.

\Image[https://upload.wikimedia.org/wikipedia/commons/f/fb/Uranium-hexafluoride-3D-vdW.png]
{title=Ball model of <uranium hexafluoride>}
{description=Hex <sublimates> at around 56.5 °C at so it can be converted to a gas relatively easily. It is then in its gas form that it is used for <uranium enrichment>}

\Image[https://upload.wikimedia.org/wikipedia/commons/9/94/Uranium_hexafluoride_crystals_sealed_in_an_ampoule.jpg]
{title=<Solid> <uranium hexafluoride>.}

= Uranium ore
{parent=Uranium}
{title2=UO\sub[2]}
{wiki}

= Uraninite
{parent=Uranium ore}

= Pitchblende
{synonym}
{title2}

This is the mineral that <Pierre and Marie Curie> used to discover <polonium> and <radium>.

\Video[https://www.youtube.com/watch?v=y-FuqptTZow]
{title=The Most Dangerous Rock in the World by Welch Labs}
{description=
OK, the title is quite minimalistic, he goes on to talk about the full early history of <nuclear fission>!
* https://youtu.be/y-FuqptTZow?t=433 <semi-empirical mass formula>
}

= Uranium isotope
{parent=Uranium}
{tag=Isotope}
{wiki=Isotopes of uranium}

= Uranium-233
{parent=Uranium isotope}
{title2=160 ky}
{wiki}

Produced as part of the <thorium fuel cycle>.

= Uranium-235
{parent=Uranium isotope}
{title2=700 My}
{wiki}

= Uranium-238
{parent=Uranium isotope}
{tag=Decay chain}
{title2=4 Gy}
{wiki}

= Uranium 238 decay chain
{parent=Uranium-238}
{tag=Decay chain}

\Image[https://upload.wikimedia.org/wikipedia/commons/6/65/Decay_chain%284n%2B2%2C_Uranium_series%29.svg]
{title=<Uranium-238> <decay chain>}
{height=1200}

= Enriched uranium
{parent=Uranium}
{wiki}

= Uranium enrichment
{synonym}

= Uranium glass
{parent=Uranium}
{tag=Glass}
{tag=Fluorescence}
{wiki}

<Glass> with <Uranium> added to it to become <fluorescent> due to <Uranium>'s chemical properties. This is unrelated to <Uranium>'s nuclear properties.

However it was this <fluorescence> that led <Henri Becquerel> to discover <radioactivity> while studying <fluorescence>, which led him to have <Uranium> compounds and <photographic> material in close proximity. I love science I guess.

\Image[https://en.wikipedia.org/wiki/File:Vasline_glass_glowing.jpg]

= Plutonium
{parent=List of chemical elements}
{title2=Pu}
{title2=94}
{wiki}

Vs <uranium>: <uranium vs plutonium Quora answer by Ciro Santilli>.

What a material:
* only exists in trace amounts in nature,but it can be produced at kilogram scale in <breeder reactors>
* it is only intentionally produced for one application, and one application only basically: <nuclear weapons>

\Video[https://www.youtube.com/watch?v=SlV45HbJm4c]
{disambiguate=plutonium}
{description=<Plutonium> for self-respect scene from the <1987 film Edge of Darkness>}

\Video[https://www.youtube.com/watch?v=ssH9o32CZtg]
{title=Burning and Extinguishing Characteristics of Plutonium Metal Fires by RobPlonski}
{description=Commented by this dude: https://www.linkedin.com/in/robplonski/}

= Plutonium extraction from Uranium
{parent=Plutonium}
{tag=Uranium}
{tag=Chemical extraction}

= PUREX
{c}
{parent=Plutonium extraction from Uranium}
{wiki}

\Video[https://www.youtube.com/watch?v=tBlqv2AcpQI]
{title=<Plutonium> Metal Preparation by <Los Alamos National Laboratory>}
{description=Describes conversion from Plutonium nitrate to a plutonium metal slab, which is then sent to final <pit (nuclear weapon)>.}

= Plutonium isotope
{parent=Plutonium}
{tag=Isotope}

= Plutonium-238
{parent=Plutonium isotope}

Strong <alpha emitter>. Can be used as an <atomic battery>.

\Image[https://upload.wikimedia.org/wikipedia/commons/7/71/Plutonium_pellet.jpg]
{title=<Plutonium-238>-oxide pellet glowing under its own heat}
{description=Unlike for nuclear applications, we don't need the pure metal, so the oxide \sup[238]PuO\sub[2] is used instead as it is more chemically stable.}

= Plutonium-239
{parent=Plutonium isotope}
{wiki}

This is the <isotope> that is produced for <nuclear weapons> by irradiating <Uranium-238> with a <neutron>.

<Plutonium-240> is a contaminant.

= Weapons-grade plutonium
{parent=Plutonium-239}
{tag=Weapons-grade nuclear material}
{wiki=Weapons-grade_nuclear_material#Weapons-grade_plutonium}

= Plutonium-240
{parent=Plutonium isotope}
{wiki}

This <isotope> shows up as an inevitable contaminant in <Plutonium-239> for <nuclear weapons>, because it emits <neutrons> too fast and makes it harder to assemble the critical mass without <fizzle (nuclear explosion)>.

It is the presence of this contaminant that made <implosion-type fission weapon> a necessity: <Gun-type fission weapons don't work with plutonium>{full}.

<Wikipedia> explains that Pu-240 is formed by Pu-239 <Neutron> capture:
> About 62% to 73% of the time when \sup[239]Pu captures a neutron, it undergoes fission; the remainder of the time, it forms 240Pu.
so its presence is inevitable.

= Chemical substance
{parent=Chemistry}
{wiki}

= Substance
{synonym}

= Chemical compound
{parent=Chemical substance}
{wiki}

The definition does not include <homonuclear molecules> which is a pain.

= Chemical explosive
{parent=Chemical compound}
{tag=Explosive}

= Gunpowder
{parent=Chemical explosive}
{wiki}

= Dynamite
{parent=Chemical explosive}
{wiki}

= Intermetallic
{parent=Chemical compound}
{wiki}

= Ionic compound
{parent=Chemical compound}
{wiki}

= Salt
{disambiguate=chemistry}
{parent=Ionic compound}

= Homonuclear molecule
{parent=Chemical compound}
{wiki}

= Allotrope
{parent=Homonuclear molecule}
{wiki}

Single <chemical element>, single phase (usually solid), but different 3D structures.

The prototypical examples are the <allotropes of carbon> such as <diamond> vs <graphite>.

= Nutrient
{parent=Chemical compound}
{wiki}

= Carbohydrate
{parent=Nutrient}
{wiki}

= Carbohydrate loading
{parent=Carbohydrate}
{wiki}

= Sugar
{parent=Carbohydrate}
{wiki}

We define a "sugar" as either of:
* <monosaccharides>
* <disaccharides>
because these are small <carbohydrates>, and they taste sweet to <humans>.

= Monosaccharide
{parent=Carbohydrate}
{tag=Sugar}
{wiki}

= Glucose
{parent=Monosaccharide}
{wiki}

The most important on in <metabolism> internals, everything else gets converted to it before being processed in the .

= Fructose
{parent=Monosaccharide}
{wiki}

= Disaccharide
{parent=Carbohydrate}
{tag=Sugar}
{wiki}

= Sucrose
{parent=Disaccharide}
{wiki}

= Fatty acid
{parent=Nutrient}
{wiki}

= Essential fatty acid
{parent=Fatty acid}
{tag=Essential nutrient}
{wiki}

= Human essential fatty acid
{parent=Nutrient}
{tag=Human essential nutrient}

= Essential nutrient
{parent=Nutrient}
{wiki=https://en.wikipedia.org/w/index.php?title=Nutrient&oldid=1075972831#Essential}

<Nutrient> that a given species cannot produce and must ingest in its diet.

= Human essential nutrient
{parent=Essential nutrient}
{tag=Human molecular biology}

https://en.wikipedia.org/w/index.php?title=Nutrient&oldid=1075972831#Essential gives somewhat of an overview:

= Essential amino acid
{parent=Essential nutrient}
{wiki}

= Human essential amino acid
{parent=Essential amino acid}
{wiki}

= Mineral
{disambiguate=nutrient}
{parent=Essential nutrient}
{wiki}

= Human mineral
{parent=Mineral (nutrient)}
{tag=Human essential nutrient}

\Include[vitamin]{parent=essential-nutrient}

= Organic compound
{parent=Chemical compound}
{tag=Organic chemistry}
{wiki}

= Organic compound identification
{parent=Organic compound}

= List of organic compounds
{parent=Organic compound}

= Benzene
{parent=Organic compound}
{title2=C\sub[6]H\sub[6]}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/thumb/5/5a/Benzene-aromatic-3D-balls.png/542px-Benzene-aromatic-3D-balls.png]
{title=<Ball-and-stick model> of <benzene>}

\Video[https://www.youtube.com/watch?v=NmzMoE3LQHM]
{title=The FASCINATING 200-Year History of <Benzene> by Chemistorian}
{description=Interesting history. Notably how things were only finally well settled by <X-ray crystallography>.}

= Methane
{parent=Organic compound}
{title2=$CH_4$}
{wiki}

= Ethanol
{parent=Organic compound}
{title2=C\sub[2]H\sub[6]O}
{wiki}

= Capsaicin
{parent=Organic compound}
{title2}
{wiki}

Active compound in pepper.

= Nitroglycerin
{parent=Organic compound}
{wiki}

= Poison
{parent=Chemical compound}
{wiki}

= Chemical weapon
{parent=Poison}
{wiki}

= Blood agent
{parent=Poison}
{wiki}

= Hydrogen cyanide
{parent=Blood agent}
{tag=Hydrogen compound}
{tag=Nitrogen compound}
{title2=$\text{H}-\text{N}\equiv\text{O}$}
{wiki}

\Image[https://upload.wikimedia.org/wikipedia/commons/thumb/9/96/Hydrogen-cyanide-3D-balls.svg/1024px-Hydrogen-cyanide-3D-balls.svg.png]
{title=<Ball-and-stick model> of <hydrogen cyanide>}

= Nerve agent
{parent=Poison}
{wiki}

= Sarin
{parent=Nerve agent}
{title2=1938}
{wiki}

= VX
{disambiguate=nerve agent}
{c}
{parent=Nerve agent}
{title2=1952}
{wiki}

= Organic chemistry
{parent=Chemistry}
{wiki}

= Biochemistry
{parent=Organic chemistry}
{wiki}

https://iubmb.onlinelibrary.wiley.com/doi/full/10.1002/bmb.2002.494030030067 Surprises and revelations in biochemistry: 1950-2000 by Perry A. Frey (2006). This should be worth a read.

= Biochemist
{parent=Biochemistry}
{tag=Chemist}

= Frederick Sanger
{c}
{parent=Biochemist}
{wiki}

= Fred Sanger
{c}
{synonym}

Ah, this seems like a nice dude.

\Video[https://www.youtube.com/watch?v=6oAsZK4EGNI]
{title=<Fred Sanger> 1918-2013 by Birgitta Olofsson (2013)}
{description=
This is a good video especially is you know <Cambridge>, to help situate Sanger's places a bit. Good Sanger quote at the end:
> I always tell people, it is much easier to get the second one than the first
}

= Peter D. Mitchell
{c}
{parent=Biochemist}
{tag=Nobel Prize}
{wiki}

= Peter Mitchell
{c}
{synonym}

<Power, Sex, Suicide by Nick Lane (2006)> paints a colorful picture of the man!
* https://www.nobelprize.org/prizes/chemistry/1978/mitchell/biographical/
* https://www.nature.com/articles/46903

= Ox Phos wars
{c}
{parent=Peter D. Mitchell}

= Chemical company
{parent=Chemistry}
{wiki}

= DuPont
{c}
{parent=Chemical company}

They made <gunpowder>. Then the <American Civil War> came. Billions, baby.

Military links carried over well into <World War II>, where e.g. they built the <B Reactor>.

= Chemical reaction
{parent=Chemistry}
{wiki}

= Reaction rate
{parent=Chemical reaction}
{wiki}

= Activation energy
{parent=Reaction rate}
{wiki}

= Catalysis
{parent=Reaction rate}
{wiki}

= Catalyst
{synonym}

= Catalyse
{synonym}

= Catalyses
{synonym}

= Electrolysis
{parent=Catalysis}
{wiki}

= Electrolyse
{synonym}

= Total synthesis
{parent=Chemical reaction}
{wiki}

TODO why can't we produce <organic compounds> more cheaply by total synthesis than biosynthesis?

= Semisynthesis
{parent=Total synthesis}
{wiki}

= Cell-free protein synthesis
{parent=Total synthesis}
{wiki}

= Chemical process
{parent=Chemical reaction}
{wiki}

= Extraction
{disambiguate=chemistry}
{parent=Chemical process}
{wiki}

= Chemical extraction
{synonym}

= Sample preparation
{parent=Chemical process}
{wiki}

= Chemical process design
{parent=Chemical process}

https://en.wikipedia.org/wiki/Process_design

\Video[https://www.youtube.com/watch?v=gkj-FZOldpI]
{title=Computer Aided Simulation & Design in Chemical Engineering by Chemical Engineering Guy (2016)}
{description=Interesting overview of the different types of modelling software used in chemical process design.}

\Video[https://www.youtube.com/watch?v=9jRfAJJO7mM]
{title=How to Design a Total Synthesis by Mike Christiansen (2013)}
{description=Just a ultra quick <hello world> with some very basic ideas, but worth watching.}

\Video[https://www.youtube.com/watch?v=rbhkAu5mgis]
{title=SuperPro Designer: Fermentation Simulation by LearnChemE (2012)}

= Chemical process design software
{parent=Chemical process design}

\Video[https://www.youtube.com/watch?v=mcbbWn4F1lQ]
{title=Process Simulation Software FREE Download - Aspen Hysys versus DWSim | COCO by Jeferson Costa (2020)}
{description=Jeferson, a <Brazilian> from <#Petrobras>, is the creator of the open source DWSim software, and in this video he  gives a quick demo of his software and compares it briefly to <aspen HYSYS>, which appears to be the golden paid reference implementation.}

= Aspen HYSYS
{parent=Chemical process design software}
{wiki}

\Video[https://www.youtube.com/watch?v=mcbbWn4F1lQ]
{title=Aspen Hysys Introduction by Emmanuel Oloyede (2016)}
{description=Holy crap, the UI is identical to Microsoft Word with that huge top bar!!!}

= Retrosynthetic analysis
{parent=Chemical process design}
{wiki}

= Entropy of a chemical reaction
{parent=Chemical reaction}
{tag=Entropy}

First, experiments, please how do you determine it and how it helps predict the future: https://chemistry.stackexchange.com/questions/42066/is-there-a-way-to-experimentally-measure-entropy

No <YouTube> video? Really?

= Electrochemistry
{parent=Chemistry}
{wiki}

= Electric battery
{parent=Electrochemistry}
{wiki}

= Battery
{synonym}

= Available battery voltages
{parent=Electric battery}
{wiki}

Only certain battery voltages exist, because this voltage depends intrinsically on the battery's chemical composition.

https://learn.sparkfun.com/tutorials/battery-technologies/all (<CC BY-SA>) has a very good summary list, reordered from lowest to highest voltage:

|| Battery Shape
|| Chemistry
|| Nominal Voltage
|| Rechargeable?

| AA, AAA, C, D (Rechargeable)
| NiMH or NiCd
| 1.2V
| Yes

| AA, AAA, C, and D
| Alkaline or Zinc-carbon
| 1.5V
| No

| Coin Cell
| Lithium
| 3V
| No

| Silver Flat Pack
| Lithium Polymer (LiPo)
| 3.7V
| Yes

| <Nine-volt battery>[9V]
| Alkaline or Zinc-carbon
| 9V
| No

| Car Battery
| Six-cell lead acid
| 12.6V
| Yes

Bibliography:
* https://www.quora.com/Why-cant-I-buy-a-5v-battery
* https://electronics.stackexchange.com/questions/219457/why-rechargeable-batteries-use-1-2v

= Nine-volt battery
{parent=Electric battery}
{wiki}

= Weston cell
{parent=Electric battery}
{wiki}

* https://youtu.be/HQ1lrEQsj4c?t=51 shows Fluke 731B Voltage Standard which contains 1.018 values due to Weston cell voltage standard

= NFPA 704
{c}
{parent=Chemistry}
{wiki}

= Fire diamond
{synonym}
{title2}

= How can a chemical substance be unstable but not flammable?
{parent=NFPA 704}

I can't believe there isn't a <YouTube> video comparing various substances for each flammability and instability ratings, this would be a huge hit.

= pH
{c}
{parent=Chemistry}
{wiki}

= pH strip
{c}
{parent=pH}
{wiki}

= Periodic table
{parent=Chemistry}
{wiki}

= Noble gas
{parent=Periodic table}
{wiki}

= Discovery of the noble gases
{parent=Noble gas}

Discovering them was not so easy because they don't form <chemical compounds>. So they exist only as gases. And <Helium> disperses off into space.

<Argon> was the first to be found by density considerations because it is so abundant on <Earth's atmosphere> (~1%): <Argon is abundant on Earth's atmosphere because it comes from the decay of Potassium-40>.

Then basically all of the others were discovered by <spectral lines>. <Helium> notably was first found on the <Sun> like that, and only later on Earth! Thus its name. Pretty cool.

\Video[https://www.youtube.com/watch?v=loqudG71uBM]
{title=The Incredible Discovery of the LEAST Reactive Elements by Chemistorian}
{description=2024. Great video.}

= History of chemistry
{parent=Chemistry}
{tag=History of science}
{wiki}

= History of chemistry bibliography
{parent=History of chemistry}
{tag=Chemistry bibliography}

= History of chemistry documentary
{parent=History of chemistry bibliography}
{tag=Documentary film}

Lists:
* <Reddit>:
  * https://www.reddit.com/r/chemistry/comments/1hddrh/have_you_ever_come_across_a_good_documentary/
  * https://www.reddit.com/r/chemistry/comments/o11eba/good_chemistry_documentary/

= The Mystery of Matter
{c}
{parent=History of chemistry documentary}
{tag=Good documentary film}
{tag=PBS program}
{title2=2015}
{wiki}

Homepage: http://www.mysteryofmatter.net

Very good documentary! Explains things very well! Great acting and wardrobe too.

Particularly tasteful is their choice of native speaker actors who speak their native language for less important narration, and English with an accent for more important moments, in particular when talking solo to the camera.

\Video[https://www.youtube.com/watch?v=z3Gt5IOjAuc]
{title=<The Mystery of Matter> episode 1}

\Video[https://www.youtube.com/watch?v=wbuDmY5gpXQ]
{title=<The Mystery of Matter> episode 2}
{description=
Covers:
* <#Dmitri Mendeleev>
* <Marie Curie>
}

\Video[https://www.youtube.com/watch?v=GWQZE0HPoAY]
{title=<The Mystery of Matter> episode 3}

= Chemistry: A Volatile History
{c}
{parent=History of chemistry documentary}
{tag=Show hosted by Jim Al-Khalili}
{title2=2010}
{wiki}

This is OK, but definitely inferior to <The Mystery of Matter> overall because it is much more interesting to watch period reenactments than <Jim Al-Khalili> going places. But the latter also has its value.

= Chemistry bibliography
{parent=Chemistry}

= Periodic Videos
{c}
{parent=Chemistry bibliography}
{tag=YouTube channel}
{wiki}

https://www.youtube.com/channel/UCtESv1e7ntJaLJYKIO1FoYw

= Chemistry database
{parent=Chemistry bibliography}
{wiki=List_of_chemical_databases}

= Free chemistry database
{parent=Chemistry database}

= Free phase diagram database
{parent=Free chemistry database}

* https://www.reddit.com/r/materials/comments/b7bchl/is_there_any_official_database_for_phase_diagrams/ being under `r/materials` the answers seem to focus on <composition phase diagram> rather than <temperature-pressure phase diagrams>

= PubChem
{c}
{parent=Free chemistry database}
{wiki}

https://pubchem.ncbi.nlm.nih.gov/