Page 141 - Science Course 2 (Book 1)

Mo5-L2b : What is a Polar Molecule?

Chemical formulas and molecular models provide information about molecules.

Chemical Formula
A carbon dioxide molecule is made up of carbon(C)
and oxygen (O) atoms.
CO Dot Diagram

2 • Shows atoms and •• •••• •• •• ••
O C O •• ••
valence electrons
A symbol without a The 2 indicates two
subscript indicates one atoms of oxygen. Each Structural Formula
atom. Each molecule of molecule of carbon • Shows atoms and
carbon dioxide has one dioxide has two oxygen lines; each line
carbon atom. atoms. represents one O C O
shared pair of
SUMMARY electrons
What is a Polar Molecule?
Ball-and-Stick Module
• Balls represent atoms
A chemical formula is one way to show the and sticks represent
elements that make up a compound. bonds; used to show
bond angles.
CO

2 Space-Filling Model
Water is a polar molecule because the • Spheres represent
oxygen and hydrogen atoms unequally share atoms; used to show
three-dimensional
electrons. arrangement of atoms.

Mo5-L2: Vocabulary Review

Direction: Complete this chart by providing an example for each term below. Then write a brief definition.

Term Example and Definition
Bond 1.

Chemical formula 2.

Covalent bond 3.

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