haileysmallwood1
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OFFERING 99 POINTS AND BRAINLIEST TO BEST ANSWER!!!

How many valence electrons are in an atom with the electron configuration in example A? Example A: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 4p^2

A. 22
B. 2
C. 4
D. 6

Respuesta :

The x number in ^x indicates the number of electronics in an obit, e.g. 1s^2 means there are 2 electrons in the 1s orbit.


Total number of electrons in A = 2 + 2 + 6 +2 + 6 + 2 + 2

= 22

VALENCE electrons are those in the outer most shell.

In A, there are 4s^2 + 4p^2: 2 + 2 = 4


Answer should be C instead. So sorry for the mistake earlier!

Example A: 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 4p^2

counting e-:    2       2        6      2       6       2      2

2+2+6+2+6+2+2 = 22

ans is A. 22