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Question
From the standpoint of atomic structure, what determines which elements will be the first and which the last in a period of the periodic table?
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Solution
- The periodic table is based on the atomic number of an element.
- Furthermore, the valence electrons determine their position in the group.
- Elements with one valence electron are classified as the first group, elements with two valence electrons as the second group, and vice versa.
- An element with 8 valence electrons belongs to the Periodic Table's last group (18th group) (excluding He).
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