Question

what is the common feature of the electronic configuration of the elements at the end of period 2 and period 3

Answer 1

Answer: The last elements of these periods have fully filled electronic configurations.

Explanation:

The last elements of period 2 and period 3 are Neon and Argon.

The electronic configurations for these elements is:

For Neon: $1s^22s^22p^6$

There are 8 valence electrons in this element and hence, has fully filled electronic configuration and is a stable element.

For Argon: $1s^22s^22p^63s^23p^6$

There are 8 valence electrons in this element and hence, has fully filled electronic configuration and is a stable element.

Therefore, the last elements of these periods have fully filled electronic configurations.

Answer 2

Answer:

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Explanation:

upar wala Shi hai

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