Question

what is the highest no. of electros in the 3rd shell of an atom? 8 or 18.
$2n ^2 \\ n = 3 \\ 2 \times 3 \times 3 = 18$
according to the formula it is 18 but we usually consider it as 8. Why????​

Answer 1

Answer:

18

Explanation:

each shell can contain only a fixed number of electrons the first shell can hold upto two electrons the second can hold up to 8 (2+6)electrons,the third shell can hold upto 18 (2+6+10) electrons, and so on.