The island of stability
white circle is set at around 180 neutrons. Through these predictions, it is clear that, following the trend, some forms of isotopes exist that are more stable than their adjacent isotopes as the island of stability begins to take shape. These superheavy elements could potentially become very effective in nuclear reactors forming (if produced in bulk) a saviour for the current energy crisis. Not only that, but studying these impossible elements improves our understanding of the attributes of elements further in the periodic table, as some of these new elements have already begun to challenge our current understanding of the periodic table. For instance, Oganesson (element 118) currently sits at the end of the periodic table and is stated to have a full outer shell making it a member of the noble gases. However, study into Oganesson reveals that it could potentially be a reactive solid, 4 shattering our view of how these new elements can potentially exist and react in our world. This revelation makes predicting the properties and effects of elements beyond the periodic table increasingly hard, as we could find any range of combination of characteristics for these new atoms. Despite this, we can easily assume that they will all be extremely reactive due to the high distance and shielding of the outer electrons. The concept of the ‘ island of stability ’ was first introduced by Glenn Seaborg in the late 1960s. He claimed that because nucleons could be arranged into shells, similar to electrons, in a concept known as the nuclear shell model where the nucleons exist with their own energy levels, some nuclei would become more stable due to them having a full energy shell. This theory of full shells within the nucleus led to the concept of magic numbers of nucleons, where the magic numbers include 2, 8, and 20. When these shells are full the nucleus is more stable as the binding energy is greater. The magic numbers currently extend to 126, though184 is believed to be very likely as a magic number. 5 More recently, evidence revealing that the island of stability might soon become a tangible place arose in the synthesis of element 117, Tennessine. Although the Tennessine produced had a very short half-life of roughly 50 thousandths of a second, its decay (via alpha decay) continued until Lawrencium-266 (element 103) was obtained. While most isotopes of Lawrencium exist with an order of seconds, Lawrencium-266 had a half-life of 11 hours, an extremely long time for an element of its size. 6 Therefore, despite Lawrencium-266 being surrounded by a sea of instability, it begins to bring hope that some form of superheavy elements can exist outside of a miniscule timeframe. Due to the nature of the theory, there are several possible locations for the island of stability. The main three are around the atomic numbers 114, 126, and even possibly 164. However, these numbers require much greater neutron numbers; for instance, 114 would require 184 neutrons. This dependency on a high neutron-to-proton ratio stems from the concept that the protons will have a repulsive force on one another against their positive charge. Therefore, if a nucleus were to exist of only protons (excluding hydrogen), the repulsion would be too great, and the nucleus would become very unstable and blow apart due to the repulsion. If there were too many protons compared to neutrons, the nucleus would also be unstable. However, it would be more likely to decay in order to lower the proton-to-neutron 4 Author Name not Stated on Website ‘ Oganesson’ Oganesson Element | Uses, Facts, Physical & Chemical Characteristics (periodic-table.com) consulted 19/08/2022. 5 Nick Connor ‘What is Nuclear Shell Model – Shell Model Of The Nucleus – Defini tion’ What is Nuclear Shell Model - Shell Model of Nucleus - Definition (periodic-table.org) consulted 19/08/2022. 6 Clara Moskowitz ‘ Element 117 hints at ‘island of stability’ on periodic table’ Element 117 hints at 'island of stability' on periodic table | Nature consulted 19/08/2022.
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