Valence Electrons and Lewis Dot Diagrams*

What is on a Lewis dot diagram besides the dots?

The atomic symbol for the element

How many valence electrons do the alkalai metals have?

1

Which group on the periodic table has 3 valence electrons?

13 or 3A (IIIA)

How many valence electrons does Pb (82) have?

4

How may dots does the diagram for P have? Draw it.

5

Lewis Dot Diagram

A method for representing an atom's valence electrons using dots around the element symbol.

What is the octet rule?

All atoms want to obtain the electron configuration of a noble gas = 8 valence electrons! The all want to have 8.

valence electrons

Electrons on the outermost energy level of an atom

One way to depict the number of valence electrons is through an electron dot diagram. What else is it called?

Lewis dot diagram.

Can you just randomly put dots on the diagram?

No. Put a dot on each side of the symbol. You must follow the order that electrons fill orbitals. (one dot pair, then single dots until each side has at least one)

Rules for Lewis Dot Diagrams

Once you start, continue clockwise or counter clockwise filling in one pair of valence electron dots, then one valence electron dot on each side before creating another pair.

The number of valence electrons in an atom determines whether or not the atom will form chemical bonds with other atoms. In other words valence electrons determine

Reactivity

Chemical properties of an element depend on....

The number of valence electrons

The electrons in the outermost energy level of an atom are called

Valence electrons

What do the dots represent on a Lewis dot diagram?

Valence electrons

Energy shell or level

an orbit followed by electrons around an atom's nucleus

Elements in the same group have

same number of valence electrons