How do the number of valence electrons differ across a period?

1 Answer
Jun 15, 2017

Answer:

The number of valence electrons increases sequentially.......

Explanation:

The number of valence electrons increases sequentially.......across the Periodic Table, from left to right as we face the Table.

And take the first Period; hydrogen has ONE valence electron; and helium has TWO valence electrons. And clearly the number of valence electrons influences the reactivity of the element.

And start a new Period, lithium (#"Group 1"#) has ONE valence electron; beryllium (#"Group 2"#) has TWO valence electrons; boron (#"Group 13"#) has THREE valence electrons; carbon (#"Group 14"#) has FOUR valence electrons......................