Francium has 87 electrons; one is the valence electron.
Argon has 10 core electrons. Subtract the amount of valence electrons from your total amount of electrons. 18-8= 10
Francium has 87 electrons but the atom is neutral.
Calcium has a total of two valence electrons.
The beryllium atom has 4 electrons and the valence is 2.
Helium has 2 electrons (total of 2 electrons and 2 valence electrons)
Valence electrons are the total amount of electrons on the outermost shell of an atom. Meaning if the last shell has two, the valence electrons are two. But a complete valence shell would hold eight.
Valence electrons are on the external shell.
Boron has 3 valence electrons out of five total electrons.
14 total electrons. 5 valence electrons.
Si (silicon) is in the fourth group, has 14 total electrons, and four valence electrons.
Silicon has a total of 10 core electrons and 4 valence electrons.
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