Electron Dot Diagram and Bonding Rules
I. Electron Dot Diagrams
A. The valance electrons go around the symbol of the element in the
following order:
1 5
4 Ea
2
8 y
6
3 7
B. To find the valance electrons of the element, find the element on
the periodic table.
1) Find out column/family the element is in by going to the top of
the column.
2) At the top of the column you will see a number above the first
box of the column, that number is the column number.
3) Find the column number in the table below. Go to the second
column in the table to find the valance electrons for the element.
4) Put the valance electrons around the symbol for the element as
shown in Part A.
Column Number
II. Bonding
1 (Alkali Family)
2 (Alkaline Earth
Family)
13 (Boron Family)
14 (Carbon Family)
15 (Nitrogen Family)
16 (Oxygen Family)
17 (Halogen Family)
18 (Noble Gases)
Valance Electron
Number
1
2
3
4
5
6
7
8
Rules
A. Find the element's symbols from the periodic table and write it down
B. Find the oxidation number for the elements by finding what column
the elements are in on the periodic table.
1) Find that column number on the table below. Go to the second
column in the table to find the oxidation numbers.
Column Number
1 (Alkali Family)
2 (Alkaline Earth
Family)
13 (Boron Family)
14 (Carbon Family)
15 (Nitrogen Family)
16 (Oxygen Family)
17 (Halogen Family)
18 (Noble Gases)
Oxidation
Number
+1
+2
Valance Electron Number
+3
-4
-3
-2
-1
0
3
4
5
6
7
8
1
2
C.
Draw an X under the symbols and drop the symbols
H-1 F-1
H
F
D. Drop the oxidation numbers to the opposite symbol and make the
oxidation number a subscript.
H-1 F-1
H1 F1
E. Check if you can reduce the subscripts
F. Name the Compound. If the elements are not polyatomic the first
symbol's name stays the same and the second symbol you add an -ide too
it. (eg) Hydrogen Fluoride
1) If you have a polyatomic molecule, the first symbol keeps its
name and if the second symbol is a polyatomic molecule you keep the ate. (eg) Ammonium Chloride (Ammonium is the polyatomic molecule) (eg)
Magnesium Phosphate (Phosphate is the polyatomic molecule)
G Do an electron dot diagram for the bond
1) Write the symbol of the first element given
2) Put the element's Valance electrons around it (See Table 2, 3rd
column)
3) Write the second element's symbol to the left of the first symbol
4) Put the element's Valance electrons around it (See Table 2, 3rd
column)
5) Draw bonds by using arrows to move free electrons.
6) After drawing the first bond, look to see if the magic number of 8
was reached for the bond. (See if both elements now have 8 valence
electrons)
a) If both elements have 8 valence electrons after the bond,
proceed to step 9. If one of the elements does not have 8 valance
electrons proceed to step 7.
7) Go to the right side of the first element, see if there is a pair
of electrons on this side.
a) If there is a pair of electrons on this side, look at the top
of the first element to see if there is a pair of electrons on this
side. If there is not, make a bond. If there is go to the bottom of
the first element and make a bond.
8) Make sure all atoms of the elements are used. Repeat step 7 until
all atoms of each element are used and each element has reached the
magic number of 8 valance electrons through bonding.
9) In covalent bonds tell me if the bond is polar (bent shape in your
electron dot diagram-you used the top or bottom of the first element)
or non-polar (You only used the left and/or right side of the first
element).