Chlorine has 17 electrons. According to the modern atomic theory, how many electrons are found in n = 2?

8 electrons

Explanation:

According to the modern atomic theory, the electronic configuration of chlorine (e⁻ = 17, Z = 17) is:

1 s²             → 2 electrons

2 s² 2 p⁶    → 8 electrons

3 s² 3 p⁵    → 7 electrons  

Total: 17 electrons

In n = 1 chlorine has 2 electrons, in n = 2 chlorine has 8 electrons and in n = 3 it has 7 electrons.

Therefore, in n = 2 chlorine has 8 electrons (2 from s orbital and 6 from p orbital).

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