How many valence electrons does an atom?

Answer 1

An atom can have anywhere from 1 to 8 valence electrons. The number of valence electrons. Elements in the first column of the Periodic Table have one electron, those in the second have two. Those in the large block ins the middle (the transition elements, the lanthanides, and the actinides are generally considered to have two valence electron , though they have a property called variable valence.

The trend of valence electrons continues in the block on the left side (the last six columns).

The first column in this block has six valence electrons, and so forth until the last column in which the elements have eight valance electrons, except for helium which has two.