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Questions
An element has its electron configuration as 2, 8, 2. Now answer the following question.
To which period does this element belong?
Which row does this element belong to?
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Solution
The element with an electron configuration of 2, 8, 2 belongs to the third period of the periodic table. The period number corresponds to the number of electron shells or energy levels occupied by electrons in an atom. Since this configuration indicates electrons in three shells (2 electrons in the first shell, 8 in the second, and 2 in the third), the element is in the third period.
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