SCIENCE JOURNAL 2018

S uper H eavy or U nnecessary ? Georgina Powell

Abstract Scientific discovery has developed greatly over the last few decades due to technological ad- vancements. It was announced on the 30 th of December 2015 that four new elements on the Periodic Table have been confirmed (Kluger, 2016). These elements are Nihonium (113- (286u)), Moscovium (115-(289u)), Tennessine (117-(294u)) and Organesson (118-(294u)) which complete the 7 th period (Compound Inter- est, 2016) (Royal Society of Chemistry , 2017).

one of the elements to 10% the speed of light and shooting it at the other element, hoping they will fuse (Kramer, 2016). However, a difficulty encountered with this procedure is the elements being synthesized have low stabilities. This is shown with Nihonium, Moscovium, Tennessine and Oganesson having half-lives of 19.6 seconds, 220 milliseconds, 51 milliseconds and 0.89 milliseconds respectively (Compound Interest, 2016). Therefore, as they are only intact for a limited time, people believe it is unnecessary to continue synthesizing elements. How an Elements Size Affects Its Stability An element’s stability is greatly affected by its size. This is due to the atomic radius and ionization energy of an element. The Atomic radius is the distance between the nucleus and its valence shell (Dictionary.com, 2018) and it influences how strong the electronegativity is which is, ‘a measure of the relative tendency of an atom to attract electrons’ (Chemistry- Dictionary.com, 2018). The protons in the nucleus of an atom attract the electrons orbiting in the electrons shells and therefore, the smaller the atomic radius, the closer these two opposite charges are and the stronger the electronegativity (Yadav, 2018). Therefore, as the atomic mass increases causing the atomic radius to increase, the weaker the pull is between the protons and electrons. This results in the ionisation energy, ‘the amount of energy required to remove an electron from an atom’ (Dictionary.com, 2018), decreasing and the ability to react with the surroundings increasing. Furthermore, isotopes are relevant to the stability of an element because an isotope’s stability is determined upon the ratio between its neutrons and protons, making some isotopes more stable than others (University of Wyoming, 2018). Additionally, the element that all the newly discovered elements decay into, Dubnium, has no stable isotopes, thus defining

Image 1: The Periodic Table’s Four New Elements

(Compound Interest, 2016)

The Method of Synthesizing Superheavy Elements A superheavy element is an element that has a higher atomic number than Rutherfordium (104) (Labmate, 2016). These elements are not naturally occurring and are manmade. This is because when they are exposed to elements lighter than rutherfordium, they react with their surroundings and undergo radioactive decay (Labmate, 2016). Therefore, they are synthetically made using a particle accelerator. This procedure occurs where two existing elements that have a sum of protons equal to the quantity of protons the element being created must have are enforced to undergo nuclear fusion by accelerating the energy of

SC J SI

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Somerset College Journal of Scientific Issues

Year 10