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Question
Write the scientific reason.
The third period contains only eight elements even though the electron capacity of the third shell is 18
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Solution
- The current periodic table consists of seven horizontal rows, known as periods. Periodic elements are ordered in increasing order of atomic numbers. The third row consists of 8 elements, with an electron capacity of 18.
- During the third period, the atomic number and number of electrons in the shell rise as you move left to right. The number of elements in the third period is determined by electronic configuration and the octet rule.
Argon (Ar) is the final element of the third period with a maximum capacity of 18 electrons. The octet of electrons is full, and because argon belongs to the zero group, the third shell has 18 electrons.Atomic No. 11 12 13 14 15 16 17 18 Elements Na Mg Al Si P S Cl Ar
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