Answer:
7 Electrons
Step-by-step explanation:
Assuming that final energy level is that same as valence shell, we first need to find how many of the electrics will be used to fill the ones before it.
Electron shell capacities are as follows :
First shell/Ebergy level: 2 electrons
Seconds shell/energy level : 8 electrons
Third shell /energy level :8 electrons
The first two shells total to 10, and the first three shells total to 18. Since chlorine (17) fills more than 2 shells but less that 3, the third one is its final energy level. We find the number in the final energy level by subtracting the 10 in the full first two. 2+8=10
17-10=7
Chlorine has 7 electrons on its final energy level.
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