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In the original 1771 experiment, Scheele used a very simple setup consisting of a glass retort with a glass receiver (round-bottom flask).
Yes, the glass was etched to some degree by the fumes, but it was not drastic enough to destroy the apparatus.
From Anders Lennartson's The Chemical Works of Carl Wilhelm Scheele [1, p. 22]:
3.1 Publication 1. ...
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Tryptophan
For instance, is there a reason 'W' specifically was chosen for tryptophan (other than the fact that 'T' was taken)?
Once you have assigned the other 19 amino acids, there are only 7 letters of the alphabet left: B, J, O, U, W, X, and Z. (Certainly not a nice Scrabble hand to have!)
If one wants to use a letter found within the name of the ...
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Neptunium (93) and plutonium (94) were so named because they followed uranium (92) on the periodic table.
Uranium was named after Uranus. German chemist Martin Heinrich Klaproth discovered uranium in 1789, eight years after William Herschel discovered Uranus. At the time, uranium was the densest element known and Uranus was the farthest planet from the sun ...
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The links provided below are to the website "Elementymology & Elements
Multidict". It is a fascinating site with information on the
discovery, naming and various other facts for each element. As the author (Peter van der Krogt) says, "I am not a chemist, but a (map) historian much interested in the origin of names". Enjoy!
A nice piece on the ...
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Sometimes it was a lucky accident, sometimes there was a lot of math and logic going in the designing experiments. The organic chemistry of that era, though, was a lot more applied and empirical than the physics of today. They usually weren't setting out to find the absolute laws-of-nature governing chemistry, they were just trying to make better dyes, ...
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I liked this question because I had never thought much about it. However, it's not such a mystery because the answer is on Wikipedia's “radical” page:
Historically, the term radical was also used for bound parts of the molecule, especially when they remain unchanged in reactions. These are now called functional groups. For example, methyl alcohol was ...
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Asked and answered, but this is a good place to include other astronomically named elements:
cerium named after the asteroid Ceres (or the Roman goddess of agriculture)
helium from the Greek helios or "Sun"
mercury OK, named after the Roman god, but so was the planet
palladium named after the asteroid Pallas, discovered the year that Pd was first isolated
...
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Some single letter codes that aren’t the amino acid’s starting letter actually make sense when viewed from certain angles. Here’s the list starting with the bloomin’ obvious:
G — Glycine
A — Alanine
V — Valine
L — Leucine
I — Isoleucine
P — Proline
S — Serine
T — Threonine
C — Cysteine
H — Histidine
M — Methionine
Some amino acids have a letter that ...
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The example that comes to mind is didymium, which turned out to be a mixture of praesodymium and neodymium. The term is still used, as far as I know, to refer to glass doped with a mixture of these lanthanides. This is discussed in one of the 'Chemistry in its element' podcast episodes.
As it turns out, wikipedia has a category called 'Misidentified ...
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(Will do more research into ammines come February.)
Premise
Ammonia is spelled with two 'm's. The more natural derivative of the word in a linguistic sense would also have the same number 'm's. Thus whichever predates the other, ammine complexes or amines, would claim the throne.
In a structural sense, when awknowledgement of the first ammine complex came ...
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Imagine a time when magnetic stirrers were unknown. You, or your lab assistant, would mix solutions in suitable glassware, shake manually, put it aside and then observe a change.
An Erlenmeyer flask is much more suitable than a simple beaker
the flat bottom gives it a stable stand on the bench
the narrrow neck allows to hold and shake a large flask with ...
answered Feb 24 '16 at 6:24
Klaus-Dieter Warzecha
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Based on research inspired by andselisk's answer, chemists stored it in glass vessels coated in wax (similar to the receiver setup Scheele used to prove the silicon dioxide precipitate was from the glassware itself.
The fourth paragraph down in this blog post on The Chronicle Flask touches on it (emphasis mine):
Where do you put something that eats ...
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The Periodic Table arranges elements in blocks as each type of orbital fills with electrons - $s,p,d,f,g,h$. Alkali metals and alkaline earths are $s$-block filling (but could be one $s$-block slot). $p$-block six electrons to fill are trelides, tetralides, pnticides, chalcogenides, halides, inert gases (but could be one $p$-block slot). Transition metal $...
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Modern day scientists rely on technology and advanced nuclear physics. But in absence of these advances, how were ancient scientists able to discover them?
In many cases, they weren't - the ancient... maybe we can't call them scientists. Let's call them "natural philosophers." The ancient natural philosophers (up until about 1700) only knew about a handful ...
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Structure elucidation via degradative studies and decomposition chemistry has sadly all but passed from the chemists' toolbox, but this was the method once used to determine molecular structures up until about half a century ago. One of my very favourite examples that I use to teach structure determination by NMR is the story of strychnine. Strychnine (below)...
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Nitrogen was originally called 'azote' by Lavoisier. This name persists in many nitrogen containing species such as azide, hydrazine, diazonium etc.
The '-ide' ending is the standard ending for anions of a single element such as carbide, oxide, sulfide etc.
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First came the Arrhenius theory. It defines an acid as a species that dissociates to produce $\ce{H+}$ in solution, and a base as a species that dissociates to produce $\ce{OH-}$ in solution. (Examples: $\ce{HCl}$, $\ce{NaOH}$)
Next came the Brønsted-Lowry theory, which expands the notion of acid and base. It defines an acid as a species that loses $\ce{H+}$...
answered Sep 3 '16 at 21:32
a-cyclohexane-molecule
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This seems like a bit of a rhetorical question, so this isn't a terribly formal or authoritative answer, but anyhow - a lot of chemical nomenclature is like lava flow. It solidified and people just worked around it.
The halogens are so named because they have a rich chemistry of ionic compounds (fluorine through iodine, anyhow). However, both the halogens ...
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Created in FORTRAN by Carroll K. Johnson, of the Oak Ridge National Laboratory (ORNL), and first released in 1965, ORTEP (Oak Ridge Thermal-Ellipsoid Plot Program) rapidly became a favorite of crystallographers and protein crystallographers to produce illustrations of structures for conference presentations and publications. A key strength of ORTEP was its ...
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One thing that was well known, even in the early days, was elemental analysis. It is Justus von Liebig’s contribution to have worked out the sum formulae of hundreds of natural compounds. This generally worked by combusting a given sample of a compound, capturing the vapours, absorbing the water with desiccants such as calcium chloride, absorbing carbon ...
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See IUPAC-IUB Commission on Biochemical Nomenclature
A One-Letter Notation for Amino Acid Sequences The Journal of Biological Chemistry Vol. 243, No. 13, pp. 3557-3559, 10 July 1968. :
The possibility of using one-letter symbols was mentioned by
Gamow and Ycas (2) in 1958. The idea was systematized by
Šorm et al. (3) in 1961. It was used by this group ...
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In 1978, the IUPAC Commission on the Nomenclature of Inorganic Chemistry decided that it would be necessary to have a systematic naming for the elements with atomic number greater than 100, even for those which had not been discovered. The recommendations are as follows:
The name is derived directly from the atomic number of the element using
the ...
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First thing, they couldn't tell elements and compounds apart. See Dalton's list of elements with their symbols.
Lime is right there--and it's not actually an element. Neither is Baryte(s). Soda and Potash probably refer to the oxides of Sodium and potassium, though terminology may have been different back then.
In those days, elements were things that ...
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Found a source here with some of the history and explanation,
Named after Ytterby, a village in Sweden near Vauxholm. Yttria – earth containing yttrium – was discovered by Gadolin in 1794. Ytterby is the site of a quarry which yielded many unusual minerals containing rare earths and other elements. This small town, near Stockholm, bears the ...
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Please note that I haven't seen the sample myself!
However, the Royal Institution claims that a bottle with the collidal gold solution is on display at Michael Faraday's Magnetic Laboratory (see bottle at the bottom of the image) in the museum of the Royal Institution.
Update
This might be nitpicking and English isn't my native language, but David ...
answered Apr 4 '15 at 10:04
Klaus-Dieter Warzecha
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10
In pharmaceutical industries, $56\%$ of the drugs currently in use are chiral molecules and $88\%$ of the last ones are marketed as racemates (or racemic mixtures), consisting of an equimolar mixture of two enantiomers.
More recently, drugs originally marketed as racemic mixtures are reintroduced using the active isomer. Examples include racemic citalopram (...
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Some sources point out the direction of the dipole moment is convention dependent. Since both conventions are mathematically correct it seems important when solving a problem to identify the convention. Both conventions seem to be derived from the bones of dead theories.
The physics convention does seem to have Franklin's work identifying negative "...
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The three-letter designation came before the single letter code. The three-letter codes themselves went several refinements and revision finally accepted by IUPAC and International Union of Biochemistry under the leadership of HBF Dixon. Later single letter codes were proposed. (apparently, because they were tiresome to write). This proposal came from Czech ...
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One attempt to order chemical elements was Döbereiner's system of triades, published in Annalen der Physik und Chemie, back in 1829 (doi 10.1002/andp.18290910217 with Wiley); or (open access with Gallica).
Although an actual view into his paper permits the speculation he was not using the atom masses we know today; rather than using specific weight and ...
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