Valence Electrons - Electrons In The Outermost Or Highest-Energy Orbitals Of An Atom

Valence Electrons - Electrons in the outermost or highest-energy orbitals of an atom.

For a chemist, the valence electrons are quite possibly the most important electrons an atom has. "Why the valence electrons?" you might ask. Well, since the valence electrons are the electrons in the highest energy level, they are the most exposed of all the electrons ... and, consequently, they are the electrons that get most involved in chemical reactions.

Types of questions:

1. What is the valence level of sulfur (atomic number 16)?

The (valence) level occurs on the third level (3). [Ne] 3s 2 3p 4 ( 2 – 8 – 6 )

2. How many valence electrons does an atom of sulfur have?

6 valence electrons ([Ne] 3s 2 3p 4 ) ( 2 – 8 – 6 )

3. How are the valence electrons in sulfur arranged in sublevels?

Simply restate the valence level as: [Ne] 3s 2 3p 4

4. How are the valence electrons in sulfur arranged in orbitals?

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3s 3p