The Dissappearing Spoon-- Chap. 3

By: Cheyenne Eckard

Synopsis of Chapter 3

Chapter three mainly focuses on the dynamic people who built the periodic table into what it is today. The chapter starts off with a well-known chemist, Robert Bunsen and his love for arsenic. After giving us a short summary of Bunsen and his scientific contributions, such as the Bunsen burner and the spectroscope the author introduces us to several other chemists that Mr. Bunsen taught. Amongst those chemists are Mendeleev, Meyer, and Lecoq de Boisbaudran. For the rest of the chapter, Bunsen, Mendeleev, Meyer, and Lecoq de Boisbaudran debate against one another for who gets to take full credit for making the periodic table. It can get quite confusing to say the periodic table was built just by one chemist because it was not.

It gets even more confusing when several elements, named lanthanides, are mined from Ytterby, in Sweden. Although, Mendeleev predicted that there were lanthanides out there, he did not physically mine them. Mendeleev often named elements before they were discovered, such as "eka-aluminium" or gallium. So should the miners that found the lanthanides get credit for discovering the new elements or should Mendeleev? However, Mendeleev could have solved this problem himself if he had traveled a few hundred miles to Ytterby and mined the lanthanides himself. The elements he would have found were cerium, yttrium, ytterbium, erbium, and terbium.

Arsenic (As)

  • Atomic #: 33
  • Atomic mass: 74.93 amu
  • Period: 4
  • Group: 15
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^3
  • Metalloid
  • Is found naturally in the Earth's crust by itself but Arsenic acid, Arsenous acid, and Arsenic trisulfide are common arsenic compounds
  • Arsenic is important because there are small traces everywhere: in ocean water, in soil, in the water and food we consume, and the air we breathe. Arsenic is used as a rodent poison, weed killers, fungicides, insecticides, and an embalming agent to preserve specimens. Arsenic usually forms a compound with either oxygen, chlorine, or sulfur.
  • Found in nature, by Albertus Magnus, and is named after the Greek name "arsenikon", which means yellow orpiment.
  • Unique characteristics are of Arsenic: is it can by yellow, black, or grey and Arsenic is poisonous at high concentrations.

Gallium (Ga)

  • Atomic #: 31
  • Atomic mass: 69.72 amu
  • Period: 4
  • Group: 13
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3hd^10 4p^1
  • Other metal
  • Gallium is not found in its elemental form on Earth, but can be found through the electrolysis of a solution of Gallium Hydroxide in Potassium Hydroxide.
  • Gallium is important because it melts at room temperature and has the largest liquid ranges of any metal. Therefore, it is used in high temperature thermometer. Gallium can be found as Gallium Arsenide and can produce laser light.
  • Dmitri Mendeleev proposed gallium's existence in 1871 based on gaps in his periodic table of elements but Paul-Emile Lecoq de Boisbaudran discovered Gallium in 1875, using Mendeleev's invention: the spectroscope. Lecoq obtained pure Gallium through electrolysis of Gallium Hydroxide in Potassium Hydroxide. Gallium is named after the Latin word for France, Gallia, because Lecoq was french.
  • Unique characteristics of Gallium: its boiling point is 3999 degrees Fahrenheit and is a silvery, glass-like metal.

Cerium (Ce)

  • Atomic #: 58
  • Atomic mass: 140.12 amu
  • Period: 6
  • Group: none
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^6 6s^2 5d^1 4f^1
  • Transition metal
  • Cerium is found in numerous minerals including allanite, monazite, bastnasite, cerite, and samarskite. Cerium is usually found on beaches of Travancore, India, and Brazil. Also, cerium can be found in the western United States, and southern California.
  • Cerium is important because it has several uses. Cerium is used as the flint in cigarette and gas lighters. Also, cerium is used in carbon-arc lighting and it is used for fluorescent lighting. cerium oxide is used to reduce carbon monoxide emissions that automobiles produce. Also, cerium is in a cream that treats and prevents infections of extensive burn wounds.
  • Cerium was discovered by Jons Jacob Berzelius and Wilhelm von Hisinger in Ytterby, Sweden, in 1803. Cerium is named after an asteroid named Ceres.
  • Unique characteristics of Cerium: it is an iron-gray color and is very reactive. If pure cerium is scratched with a knife, it will likely ignite. Also, Cerium is a rare earth metal.

Yttrium (Y)

  • Atomic #: 39
  • Atomic mass: 88.91 amu
  • Period: 5
  • Group: 3
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^1
  • Transition metal
  • Yttrium does not occur in nature by itself. Yttrium is in the mineral gadolinite. Yttrium is obtained through an ion exchange process from monazite sand. Yttrium typically exists as an ion: Y^+3.
  • Yttrium is important because Yttrium-90, a radioactive isotope, is used for the treatment of various cancers. Yttrium usually forms a compound, Yttrium oxide. Yttrium oxide is used to make a high-temperature superconductor YBCO. Also, yttrium oxide and yttrium orthovandate are combined together with europium to produce the red phosphor used in televisions with color.
  • Yttrium was discovered in Ytterby, Sweden, by Johan Gadolin, in 1789. Yttrium is named after the village it was discovered in, Ytterby.
  • Unique characteristics of Yttrium: ignites in air when heated, is silvery-white, and the moon shows a high yttrium content based on the lunar soil samples from the Apollo moon landings.

Ytterbium (Yb)

  • Atomic #: 70
  • Atomic mass: 173.04 amu
  • Period: 6
  • Group: none
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^6 6s^2 4f^14
  • Transition metal
  • Ytterbium is not found in nature by itself but is found in numerous minerals: mainly monazite, gadolinite, euxenite, and xenotime.
  • Ytterbium is important because it has many uses. An isotope of Ytterbium is radioactive, therefore, is used in portable x-ray machines that require no electricity. Ytterbium is added to stainless steel in order to improve grain refinement and strength. Ytterbium fiber laser amplifiers are used for engraving.
  • Ytterbium was discovered when Jean Charles Galissard de Merignac heated another element, erbia, and extracted Ytterbium, in Geneva, Switzerland, in 1878. Ytterbium is named after the village, Ytterby, in Sweden, in which the element that Ytterbium was extracted from was discovered.
  • Unique characteristics of Ytterbium: is a bright, soft, white-silvery metal that is malleable, is one of the rare earth metals, tarnishes rapidly in air, reacts slowly with water, and dissolves quickly in mineral acids. Also, Ytterbium is a rare earth metal.

Erbium (Er)

  • Atomic #: 68
  • Atomic mass: 167.26 amu
  • Period: 6
  • Group: none
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^6 6s^2 4f^12
  • Transition metal
  • Erbium is not an naturally occurring element but it is found in gadolinite. Erbium is most present in compounds as Er^+3. Other Erbium compounds are: Erbium oxide, Erbium fluoride, Erbium chloride, and Erbium iodide.
  • Erbium is important because it used in the nuclear power industry. Also, Erbium is added to fiber optic cables and is used in photographic filters to absorb infrared light. Erbium is used in amplifiers and lasers, as well.
  • Erbium was discovered by Carl Gustaf Mosander, in 1843, in Ytterby, Sweden. Erbium is named after erbia, the material that Erbium is extracted from. Also, it is named for the village that erbia was discovered in, Ytterby, Sweden.
  • Unique characteristics of Erbium: is bright, soft, malleable, white-silvery, slowly tarnishes in air, reacts slowly with water, and dissolves in acids. Also, Erbium is a rare earth metal.

Terbium (Tb)

  • Atomic #: 65
  • Atomic mass: 158.93 amu
  • Period: 6
  • Group: none
  • Electron Configuration: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^6 6s^2 4f^9
  • Transition metal
  • Terbium is not found in nature by itself. It is found in the material terbia.
  • Terbium is important because it has many uses. Terbium is often found as an ion, Tb^+3. Tb^+3 is used in color phosphors in lighting applications, such as trichromatic lighting, color TV tubes, and makes the green color on any electronic device with a screen. Terbium Chloride is used to check for microbes.
  • Erbium was discovered by Carl Gustaf Mosander, in 1843, in Ytterby, Sweden. Terbium is named after terbia, the material that Terbium is extracted from. Also, it is named for the village that terbia was discovered in, Ytterby, Sweden.
  • Unique characteristics of Terbium: is malleable, doesn't tarnish rapidly in air, and is soft enough to cut with a knife. Also, Terbium is a rare earth metal.

Summary

Arsenic, Cerium, Gallium, Yttrium, Ytterbium, Erbium, and Terbium are important because each of them are used for various reasons, as stated above. Also, Cerium, Ytterbium, Erbium, and Terbium are rare earth metals. Isolation of the rare earth elements from each other is difficult. Gallium, Yttrium, Ytterbium, Erbium, and Terbium played a key role in the history of science because Mendeleev predicted that those elements would be found but Lecoq actually found them. "As no less a genius than Albert Einstein once said, "It is theory that decides what what we can observe." In the end, it's probably impossible to tease out whether the heads or tails of science, the theory or the experiment, has done more to push science ahead" (chap. 3, pg. 32). So is theory more important than experiment, or vice versa? The mineral gadolinite was discovered in Ytterby, Sweden. Gadolinite contained 3 materials: yttria, erbia, and terbia. The material yttria contained two elements: Yttrium and Ytterbium. Scientists soon confused erbia with terbia because of their similar names so erbia is now called terbia and visa versa. Erbium came from the material, erbia and Terbium came from the material, terbia.

Works Cited