Module 2 Intro
1. Module 2 Intro
1.4. Page 2
Module 2—Chemical Compounds
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Bonding theory is one of the most important concepts in chemistry. Although you studied bonding theory in Science 10, it is important to review these concepts. Understanding bonding may involve revising what you currently understand. Read the descriptions of different bonding theories in your textbook, on page 78 to the bottom of page 80. List terms that are new to you. You will use this list in the Try This exercise below.
Try This
Bonding Concept Map
Prepare a concept map or other graphic organizer that connects any new terms introduced on pages 78 to 80 of your textbook.
To create a concept map, follow these steps:
Step 1: Place terms that you currently use to explain the bonding of matter on a sheet of paper. The order of the terms is not important.
Step 2: Place new terms introduced in the textbook on the sheet of paper.
Step 3: Use lines to connect related terms that appear on the sheet of paper.
Step 4: For each line you draw, write a brief statement (maximum 5 words) that links the two concepts.
Save a copy of your bonding concept map in your course folder. You may wish to share your concept map with your teacher. Later in this module you may wish to review your concept map so that you can add terms, revise linking statements, or add additional lines and linking statements.
Self-Check
So far in your study of bonding you have seen different representations for electrons associated with atoms. Review the representation for valence electrons shown in “Figure 3” on page 80 of your textbook.
SC 1. Complete the table representing the arrangement of electrons in the following atoms.
a. fluorine
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e– |
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e– |
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p+(protons) |
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F atom |
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b. magnesium
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e– |
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e– |
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e– |
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p+ (protons) |
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Mg atom |
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Self-Check Answers
SC 1.
- fluorine
7
e–
2 e–
2 e–
2 e–
1 e–
2
e–
9
p+ (protons)
F atom
- magnesium
2
e–
1 e–
1 e–
0 e–
0 e–
8
e–
2
e–
12
p+ (protons)
Mg atom
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Lewis Symbols
Earlier in this lesson you read about the theories of Gilbert Lewis. In order to support his theory, Lewis developed a model to represent the valence electrons, the electrons associated with bonding.
Read “Atomic Models: Lewis Symbols” on page 81 of your textbook.
Self-Check
SC 2. Draw a Lewis symbol for sulfur. Identify the lone pairs and the bonding electrons in your diagram.
SC 3. Explain how the location of elements on the periodic table provides information about the number of valence electrons they have.
SC 4. Draw Lewis symbols for all of the group 1 elements. How are these elements similar?
SC 5. Draw Lewis models for all of the group 16 non-metals. How are these elements similar?
Self-Check Answers
SC 2.
SC 3. The column or group number provides information about the number of valence electrons. Elements in group 1(1A) (first column) all have one valence electron. Information for other columns is listed below.
Group # |
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Valence |
1 |
IA |
1 |
2 |
IIA |
2 |
13 |
IIIA |
3 |
14 |
IVA |
4 |
15 |
VA |
5 |
16 |
VIA |
6 |
17 |
VIIA |
7 |
18 |
VIIIA |
8 |
SC 4.
They all have 1 bonding electron.
SC 5.
They all have 6 valence electrons, 2 bonding electrons, and 2 lone pairs.
Try This
TR 1. Lewis symbols, sometimes called electron dot diagrams, are static, two-dimensional representations of an atom. Lewis symbols are a convenient way to show valence electrons. In reality the electrons are in constant motion in three-dimensional space. The organization of orbitals within an energy level can have important considerations.
Use materials available to you at home or school to build three-dimensional representations of Lewis symbols. Use a digital camera or other means to keep a record of your 3-D models in your course folder. Identify what principle is involved in a three-dimensional model to represent the position of valence electrons in orbitals around the atoms. Share your answer to this question with your teacher.