Question

multiple choice: how many electrons are in the outermost shell of an atom with 15 electrons? a 5 b 10 c 2 d e 3 f 8

Explanation:

Step1: Determine electron configuration

For an atom with 15 electrons, the electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}\).

Step2: Identify outermost shell

The outermost shell is the third shell (\(n = 3\)). In the third shell, there are \(2 + 3=5\) electrons (\(3s^{2}\) and \(3p^{3}\)).

Answer:

A. 5