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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. ...


13

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 ...


10

Prigogine's Chemical Thermodynamics gives a bit more context as to why a plimsoll symbol is somewhat more preferable and is indeed used to denote non-zero nature of standard values [1, pp. xxiv, 86]: The properties of a pure substance are denoted by a superscript $^0$. The use of this symbol to denote "standard" thermodynamic quantities is then ...


7

de Brogile explains why orbitals are quantised Strictly speaking de Brogile doesn't prove Bohr's postulates which are mostly wrong. But he did provide an explanation for the most important of Bohr's ideas: electron orbitals are quantised. Bohr's whole model starts with the classical idea that electrons "orbit" a nucleus. But this has several problems not ...


4

The term "normality" stems from the older German term for equivalent concentration (die Äquivalentkonzentration), namely die Normalität, which was coined by Karl Friedrich Mohr. According to German Wikipedia which also refers to Straube's Der historische Weg der Chemie [1, p. 220], Mohr introduced the concept of normal solution and normality (as it's known ...


3

Interesting question but the sad answer is we will never know the true story. Here is the original text (thanks to Google Books) dated 1863, right from the horse's mouth Adolf von Baeyer. Dieser Gedanke hat mich bei der folgenden Arbeit geeitet (spelling?), und ich habe mich zunächst bemüht, die Kenntnis des Materials zu vervollständigen. Man wird ...


3

This image is from Atomic Spectra and Atomic Structure by Gerhard Herzberg, ‎John William Tranter Spinks - 1944. It does not really have boxes (just boxes of a table), but spin +1/2 and spin -1/2 are shown as arrows. Of course, I am not claiming this is the first usage, just that in 1944 it existed.


1

Well, interesting question, I would re-word your question as "How can one determine an atomic mass with high accuracy using gravimetric analysis? Precision simply implies that you repeated a measurement and it agrees very well with itself even though it may be wrong. What we desire is high precision and high accuracy. Almost all the naturally occurring ...


1

Rutherford conducted his gold foil in order to prove Thomson's plum pudding model but the result was contradicting. He expected that most of the Alpha particle will show very minor deflections because the positive charge was evenly spread throughout the atom according to the plum pudding model.


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