Here are the essential concepts you must grasp in order to answer the question correctly.
Valence Electrons
Valence electrons are the outermost electrons of an atom and are crucial for determining how an element interacts with others. They play a key role in chemical bonding, as they are involved in the formation of bonds with other atoms. The number of valence electrons can often be predicted based on an element's position in the periodic table.
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Group 17 Elements
Chlorine, bromine, and iodine belong to Group 17 of the periodic table, also known as the halogens. Elements in this group typically have seven valence electrons, which makes them highly reactive, as they seek to gain one additional electron to achieve a stable octet configuration. Understanding their group characteristics helps in predicting their chemical behavior.
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Periodic Table Trends
The periodic table exhibits trends in the number of valence electrons across different groups. As you move from left to right across a period, the number of valence electrons increases. For halogens, this trend is consistent, as they all have seven valence electrons, which is essential for understanding their reactivity and bonding patterns.
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