How many valence electrons are in Si 2-?

Answer 1

Si 2- actually has 4 valence electrons

Answer 2

The normal valance number of silicon is 4, so with Si 2- one knows that silicon now has 6 electrons in it's valence shell.

Answer 3

Silicon (Si) has 4 valence electrons in its neutral state. An ion with a charge of 2- indicates a gain of 2 electrons. Therefore, in Si 2-, there are 6 valence electrons.