The Galapagos of the Periodic Table

Chapter 3 Project by Jacob Williams


In chapter three, there wasn't as much focus on the elements that were mentioned, but the focus was more so directed towards the people who discovered them and some of the main contributes to what we now know as the periodic table. The seven elements that this chapter refers to are Arsenic, Gallium, Cerium, Yttrium, Ytterbium, Erbium, and Terbium. This chapter goes on to tell some of the properties of some of these elements, like that Arsenic is poisonous and that Gallium can literally melt in your hand. It goes on to tell about famous scientists such as Bunsen, who did not invent it, perfected the Bunsen Burner and invented the spectroscope, and Mendeleev, who constructed a large portion of the modern periodic table in 1869 (Chap. 3, p.47 & 50).


The atomic number for arsenic is 33 and its atomic mass is 74.9 AMU. Arsenic is in group 15 and is in period 4. The electron configuration for Arsenic is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3 (Dynamic Periodic). Arsenic is classified as a metalloid. Arsenic does occur naturally. It can be fond all over the world, but a large majority of it comes from places such as China and Chile. Arsenic was used during war times to make things like poison gasses. Arsenic was also used to make insecticides and rat poison. Arsenic is said to have been discovered in the year 2500 BCE. Arsenic got its name from a Persian word that literally meant "yellow" (Dynamic Periodic). Arsenic is toxic to humans, plants, and animals. It is said that it was used by Roman assassins to kill others by being smeared on fruits. Bunsen noted, "Arsenic, producing instantaneous tingling of the hands and feet, even giddiness and insensibility" (Chap. 3, P.47-48).


Gallium's atomic number is 31 and the atomic mass is 69.7 AMU. Gallium is in period 4 and it is in group 13. Gallium's electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1 (Dynamic Periodic). Gallium is classified as a post-transition metal. Gallium does not exist naturally by itself in nature. It can be found in high gallium minerals, but things like that are very rare. They cannot be a primary source. Gallium is used to make things like semiconductors. Semiconductors are a big part of electronic circuits Do it id important for the production of things like cell phones (Dynamic Periodic). Gallium was discovered by Paul Emile Francois Lecoq de Boisbaudran. Gallium is name after the word, "Gallia," which is the Latin word for France (Chap. 3, P. 50). An interesting thing about Gallium is that it has such a low melting point. Gallium melts at 84 degrees Fahrenheit. That means if you held Gallium in your hand, it would melt! Gallium was also a favorite for pranksters who would shape it into spoon and get others to stir their tea with it so it would melt (Chap. 3, P.54).


Cerium has an atomic number of 58. It has an atomic mass of 140.11 AMU. Cerium is located in period 6 and it is in the group of elements called the lanthanoids. Cerium doesn't have an actual number to represent its group (Dynamic Property). The electron configuration for Cerium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2 6p2. As stated before, Cerium is classified as a lanthanoid. Cerium is the most common out of all of the rare earth elements. Cerium can be found all across the Earth as it makes up about .005 percent of the Earth's by the weight (Dynamic Periodic). Cerium oxide is important to use. It is put inside self cleaning over and it is put inside of the oven walls. Cerium oxide also plays an important part in the process of refining petroleum. The first time Cerium was discovered was in the year 1803 by Jacob Berezlius and Wilhelm Hisinger. Cerium was named after one of the dwarf planets, whose name was "Ceres" (Dynamic Periodic). Cerium is a metal that is soft and is silver in color. It will spontaneously react with air that is 65-80 degrees Fahrenheit. It will also react with water (Dynamic Periodic).


The atomic number of Yttrium is 39 and the atomic mass of Yttrium is 88.9 AMU. Yttrium is in group number 3 and period number 5. Yttrium's electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d1. Yttrium is classified as a transition metal. Yttrium has never been found in nature on its own, it has only been found with rare earth metals and some of the uranium ores (Dynamic Periodic). Yttrium is important today because it goes into things like medicines and treatments. Some treatments such as Yttrium Y 90 ibritumomab tiuxetan are used to treat some types of cancers like bone cancers and leukemia. Yttrium was first originally separated from other elements in 1828 when anhydrous Yttrium chloride was heated with Potassium. It was named after a village in Sweden called Ytterby (Dynamic Periodic). Yttrium is an element that is silver in color and has similar chemical properties with the lanthanides.


Ytterbium's atomic number is 70 and its atomic mass is 173.045 AMU. Ytterbium is located in the same group of elements as Cerium which is the Lanthanides. Ytterbium is in period number 6 (Dynamic Periodic). The electron configuration of Ytterbium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14. As mentioned before, Ytterbium is classified as a lanthanoid. Ytterbium is found in rare earth elements and can be found in some rare minerals. Some of the main mining operations take place in the United States and in China. Ytterbium is important in our world today because it is used in things like stress gauges. A stress gauge is a machine that measures deformation of the ground due to things like earthquakes and explosions (Dynamic Periodic). Ytterbium was discovered by a man named Jean Charles Galissard Marignac. It was discovered in the year 1878. Jean believed that Ytterbia was actually a compound of a new element called Ytterbium. Ytterbium is a malleable metal which means that it can be molded. It also appears as a bright silver color (Dynamic Periodic).


The atomic number for Erbium is 68 and the atomic mass of Erbium is 167.259 AMU. Erbium is not in a number group, just like the element above, it is grouped with the Lanthanides. Erbium is also located in period number 6 (Dynamic Periodic). The electron configuration for Erbium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f12. Erbium is also classified as a lanthanoid. This element is never found own its own/free form in nature, but it can be found in the ores of certain types of sand. One of the leading suppliers of this element in the world is China. One industry that Erbium plays a role in is the jewelry industry. The glass that can be made from this element is often used in things like sunglasses, earrings, and other types of less expensive jewelry. Erbium was discovered in the year 1843 by a man named Carl Mosander. This element was also named after the Sweden village of Ytterby. One quality that sets Erbium apart from some of the other lanthanides is the rose-colored salts that it can form.


The atomic number for Terbium is 68 and the atomic mass for Terbium is 158.92 AMU. Erbium is in period 6 and like some other others, it does not have a group number, the group it is in is the lanthanoids (Dynamic Periodic). The electron configuration for Terbium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f9. Terbium is classified as a lanthanoid. Like many rare earth elements, this element is also found in many different types of minerals (Dynamic Periodic). Terbium is used in the production of electronic devices. It is used in some devices such as sonar systems and certain types of sensors. Terbium was discovered by Carl Mosander in the year of 1843. An interesting thing about this element is that it is so soft that you can actually cut it in to pieces with a knife.

Summary of these elements

Many of these elements that are mentioned in chapter 3 are still used in some major industries today. We may not think much of these elements because the average person may not know much about them, but if you actually look into in, they are more helpful than we realize. They are put in electronic devices that we use today such as cell phones, they help research on other elements, and they can benefit our health in some situations, such as Ytterium. Discovery of these elements has helped the discovery of other elements that we didn't know about.