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Mk
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In an atom, I always hear that it want's to have a valence shell containing 8 electrons, why?
Mk said:In an atom, I always hear that it want's to have a valence shell containing 8 electrons, why?
Elements want to have 8 valence electrons because it is the most stable electron configuration, known as the octet rule. This means that having 8 valence electrons in their outermost energy level allows the element to have a full outer shell, making it less reactive and more stable.
Atoms can achieve 8 valence electrons through various methods, such as gaining, losing, or sharing electrons. This depends on the element's position on the periodic table and the number of valence electrons it already has.
The number 8 is considered the magic number for valence electrons because it is the maximum number of electrons that can occupy the outermost energy level, known as the valence shell. This is due to the energy levels and subshells of electrons being filled in a specific order, and the 8th electron completes the level, making it the most stable configuration.
Yes, there are exceptions to the octet rule, especially for elements in the third period or higher on the periodic table. These elements can have more than 8 valence electrons due to the presence of d orbitals in their outermost energy level. Additionally, elements with fewer than 8 valence electrons, such as hydrogen and helium, can also be stable with only 2 valence electrons.
If an element does not have 8 valence electrons, it will either gain, lose, or share electrons with other elements to achieve the octet rule. This is because elements with an incomplete outer shell are more reactive and tend to form chemical bonds to become more stable.