South Pasadena  Chemistry
Name _______________________________
Period ___ Date ___/___/___
10  Bonding
VALENCE ELECTRONS /
3s
LEWIS
SYMBOLS
I
II
III
IV
V
VI
VII
VIII
Na
Mg
Al
Si
P
S
Cl
Ar
3p
3s
2p
3p
3s
2p
3p
3s
2p
3p
3s
2p
3p
3s
2p
3p
3s
2p
3p
3s
2p
3p
2p
2s
2s
2s
2s
2s
2s
2s
2s
1s
1s
1s
1s
1s
1s
1s
1s
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
Instructions:
1.
Row 2—Orbital Diagrams
Draw the orbital diagrams for the Period 3 elements (Na  Ar) in the second row of the chart.
2.
Row 3—Ground State
In Unit 10, we are concentrating on the valence electrons, in this case the 3s and 3p electrons. Re-copy the electrons from the orbital
diagram into these four circles. Label this row the “ground state”.
3.
Row 1—Lewis Electron-Dot Symbols (ground state)
Gilbert N. Lewis proposed a simple symbol to show the valence electrons. There are four valence orbitals and there are four sides to an
element’s symbol. Each valence electron can be symbolized as a dot. Here is oxygen as an example:
  
 or 
Draw dots on the symbols to match the ground state valence electrons for the Period 3 elements.
4.
Row 4—Bonding Capacity
In the next row, write the number of half-filled orbitals (orbitals with only one electron in it) in the ground state. This is called the bonding
capacity. We will find out that an atom can make a bond if it has a half-filled orbital. Each time an atom makes a bond, it releases energy
(this is a good thing).
5.
Row 5—Bonding State
If you have a filled orbital and an empty orbital, you can move one of the electrons from the filled orbital to an empty orbital. This “costs”
a little bit of energy, but it increases the bonding capacity of the element. Making bonds is good, it releases energy, so the cost is worth it.
Label this row of circles “Bonding State”.
6.
Row 6—New Bonding Capacity
In row 6, write the new bonding capacity for each element. Only three families actually change.
7.
Bottom of the page.
Draw the Lewis electron dot symbols for all of these atoms in their Bonding State. The dots should match the Bonding State Orbitals
(Row 5).
Row 6 and the elements at the bottom of the page are what you need to know for this next unit.