Here are the essential concepts you must grasp in order to answer the question correctly.
Noble Gas Configuration
Noble gas configuration refers to the electron arrangement of noble gases, which have full outer electron shells, making them stable and unreactive. Atoms tend to gain, lose, or share electrons to achieve this stable configuration, typically resembling the nearest noble gas in the periodic table.
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Electron Affinity
Electron affinity is the energy change that occurs when an atom gains an electron. Elements with high electron affinity tend to gain electrons easily, which is crucial for understanding how many electrons an atom like iodine needs to gain to reach a noble gas configuration.
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Periodic Table Trends
Periodic table trends, such as electronegativity and ionization energy, help predict how elements will behave in terms of gaining or losing electrons. For example, elements in Group 17, like iodine, typically gain one electron to achieve a stable noble gas configuration, which in this case is that of xenon.
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