13. how many valence electrons does an atom
with 5 electrons, 5 neutrons, and 5 protons
have in its ground state?
a. 5
b.
4.
c.
d.
3
2

The answer to your question is: 3

Explanation:

If an atom has 5 electrons, 5 neutrons and 5 protons, it means that the element is Boron. Boron is situated in the third group A, that means that is has 3 elements in its outermost shell.

Also, if we do the electronic configuration:

                                                                         1s² 2s²2p¹

If we count the number of electron in the second level of energy, the result will be:    2 in s and 1 in p  = 3. Those are the valence electrons.

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