ATOMIC THEORY
Lesson 3

 
PHYSICAL SCIENCES – MATTER
LESSON 3.  Chemical Bonds

 

Materials:

Worksheet
Periodic Table of Elements

 

Objective:  Students learn about the different ways that atoms and molecules chemically bond.

 

Teacher Notes:

 

In this unit students read about the evolution of the chemical bonding theory.  It is important to understand that there are many ways in which bonding can take place.  Covalent and ionic bondings are just the end members of a spectrum of bonding.   Historically, it was difficult to imagine how bonding took place.  Sophisticated instrumentation helped to unlocked some of secrets of how elements bond.

 

The worksheet is just a review to see if they understood the concepts of valences and electronegativity from the reader. 

 

1. They can share
4. 

Compound Anion Cation Difference Ionic or covalent
NaCl Na + = .93 Cl- .3.16 2.23 ionic
H2O HH+  = 2.20  = 2.20 O- = 3.44 1.24 covalent
AlCl3 Al+  = 1.61= 1.61 Cl- = 3.16 1.55 covalent
C2H2 C+ = 2.55= 2.55 H = 2.20 .35 covalent
NO3 N+ = 3.04= 3.04 O- =3.44 .40 covalent
Ca2O Ca+= 1.00= 1.00 O- = 3.44 2.44 ionic
KCl K+ = .83= 0.82 Cl- = 3.16 2.34 ionic

 

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