periodic table color coded by date discovered

#Periodic table color coded by date discovered manual#

Selenium is a semiconductor and is used in photocells. The chief commercial uses for selenium today are glassmaking and pigments. Minerals that are pure selenide or selenate compounds are known but rare. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Selenium is found in metal sulfide ores, where it partially replaces the sulfur. Selenium (from Ancient Greek σελήνη ( selḗnē) 'moon') was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). It seldom occurs in its elemental state or as pure ore compounds in Earth's crust. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic.

#Periodic table color coded by date discovered manual#

Another version of the periodic table can be found in the Starfleet Medical Reference Manual which is devoid of the 'in-jokes' found on the Next Generation version.Selenium is a chemical element it has symbol Se and atomic number 34. It is unknown if this table was also labeled with different elements than those seen in 'Rascals'. However, in at least one case, in the episode ' Cardassians' (see image on right), the table had a different color code. The table from 'Rascals' was later used for the classroom scenes on Star Trek: Deep Space Nine. This can be seen with the element poi, the heaviest element, and that its physical atomic size is much smaller than that of the element hawkeye, which is much lighter in terms of atomic weight. It is also interesting to note that the size of the atom itself (as seen in the okudagram of the Table of Elements) does not affect the atomic weight. Elements are also sorted by 'atomic weight,' and the atomic weights of the known elements differ from their actual atomic weights. It contains many in-jokes and errors, and is missing several key elements. The Table of Elements on station Deep Space 9 In 3189, Ensign Sylvia Tilly discovered minerals at a settlement on a planet which were not on the elemental table. ( TAS: ' One of Our Planets Is Missing')Ī Table of Elements was seen in a classroom aboard the USS Enterprise-D ( TNG: ' Rascals') and also in the classroom on Deep Space 9's Promenade.

In 2269, Spock stated that the matter- energy cloud had ' elements not known in our periodic tables'. On October 23, 2032, Lieutenant John Kelly recorded that after analyzing the contents of a graviton ellipse it would be necessary to make room on the periodic table. ( TAS: ' One of Our Planets Is Missing') Using the table, many elements shared a common atomic weight or symbol, and some even have multiple atomic weights or symbols and are listed twice.īenny Russell had a periodic table on the wall of his kitchen in 1953.

Multiple periodic tables were known to the Federation, though elements unknown to any of them still existed. A periodic table, also known as Table of Elements or elemental table, was a means of grouping chemical elements.