Elementymology & Elements Multidict

memory peg	Silvery heavy radioactive metal melting point 1132 °C; 2070 °F boiling point 2818 °C; 5104 °F density ~18.95 g/cc; ~1183.01 pounds/cubic foot
1789 Martin H. Klaproth, Germany
Uranus, planet, discovered 1781 and named after the Greek god of the Sky and father of the Titans

The German chemist Martin Klaproth (1743-1817) discovered in 1789 a new element in pitchblende ores from Johanngeorgenstadt in the Saxonian Erzgebirge (Metalliferous Mts.) and Joachimsthal in Bohemia (note). Pitchblende was thought to be a Zinc, Iron or Tungsten ore. First he wanted to name the element Klaprothium, after himself. But he resisted the temptation and proposed, "until a better name was found," to call his element Uranium after the last planet to have been discovered, for which the German astronomer Bode had suggested the name "Uranus" (see below).

Since Mendeleyev's periodic system did not yet exist, Klaproth would not have realized that Uranium, named after the ultimate planet, would for many years be also the ultimate element. When elements 93 and 94 were artificially made many years later, the names Neptunium and Plutonium were chosen on the analogy with the solar system.

The French scientist Henri Becquerel (1852-1908) discovered the radioactive property of Uranium in 1896. Soon many different substances were discovered emanating radiation. Before the nature of radiation was understood, before it was understood that an element can be transformed into a different element, and before the existence of isotopes was proposed, the discovery of these substances created massive confusion. Each source of radiation was around 1900 seen as a separate element. In 1900 William Crookes found that Uranium contained a substance soluble in ammonium hydroxide and ammonium carbonate, which he called Uranium X. Others found there were two Uraniums which they called Uranium 1 and Uranium 2. Uranium X₁ formed Uranium X₂. Uranium X₁ was found to produce two kinds of beta rays resulting in Uranium X₂ and Z. In 1911 Uranium Y was found. Eventually they were placed in a sequential series:

Uranium 1 → Uranium X₁ → Uranium X₂ → Uranium Z → Uranium 2 → Uranium Y.

Later was understood that this concerned a decay series and that each of the Uraniums was an isotope of a different element. In 1902 Frederick Soddy and Ernest Rutherford proposed two of these decay series, one starting with Uranium ending with Lead, and the other starting with Thorium (Ionium) and also ending in Lead (note). (See the tables at all of the elements from Thallium (#81) to Uranium (#92).

In 1913 Frederick Soddy proposed that an element emitting an α-particle is transmuted into the element two spaces to the left on the periodic table, whereas an element emitting a β-particle is transmuted into the element immediately to the right (note). For example, Uranium 1 (now ²³⁵U, atomic number 92) emits an α-particle and becomes Uranium X₁ (= ²³⁴Th, atomic number 90), and this emits a β-particle and becomes Uranium X₂ (= ²³⁴Pa, atomic number 91). The rules provide a way to understand the decay series and led to Soddy's proposal of isotopes to explain differing atomic weights for samples of the same element produced by different decay modes.

In the 19th century a native Czech name was proposed: nebesník, probably derived from "nebe" = sky.

In the fabulous ages of ancient times the appellations of Mercury, Venus, Mars, Jupiter and Saturn were given to the Planets, as being the names of their principal heroes and divinities. In the present more philosophical era it would hardly be allowable to have recourse to the same method and call it Juno, Pallas, Apollo or Minerva, for a name to our new heavenly body. The first consideration of any particular event, or remarkable incident, seems to be its chronology: if in any future age it should be asked, when this last-found Planet was discovered? It would be a very satisfactory answer to say, 'In the reign of King George the Third.

About the name of the Planet Uranus around 30,000 websites say it was given the name of the Greek God Uranus, but 300 websites say it was named after Urania (Οὐρανία), the muse of astrology. (note).

Naming after Urania would be unusual as almost all other planets have the names of Gods but Urania is a muse. But some say it could be true, since Herschel was a musician and knew the muses (note). However, Herschel did not give the name Uranus to the planet he discovered - the name is given by the astronomer Bode.

In the following reviews from the Algemeene Vaderlandsche letter-oefeningen of 1783 the different name proposals are discussed. In a note the reviewer gives as his own opinion that the naming the planet after the father of Saturnus is a good idea.

 

• James B. Calvert, "Uranium" 2002 (on-line).
• Winfried Kölzer, Radioaktivität, Strahlenexposition, Strahlenwirkung. Bonn: Informationskreis Kernenergie, 2000 (PDF file on-line).
• Philippe Hillion, La radioactivité : une épopée - Histoire - chronologie (on-line).
• Bertrand Goldschmidt, Uranium's Scientific History 1789-1939. World Nuclear Association (on-line).
• Uran und Isotope. Gmelins Handbuch der anorganische Chemie, 8. Aufl.; System-Nummer 55 (1936).
• Mary Elvira Weeks, Discovery of the Elements, comp. rev. by Henry M. Leicester (Easton, Pa.: Journal of Chemical Education, 1968), pp. 266-271.