1. Electronegativity and Bond Type

2. Electronegativity Electronegativity is a measure of how strongly an atom attracts a shared pair of electrons to itself. Fluorine has the highest electronegativity. The Noble gases do not have an electronegativity.

3. Electronegativites have been measured and can be found in tables in books.

4. The difference in the electronegativity can be used to determine the type of bond. 0.0 3.3 F-F P-H Fr-F Cs-F Perfectly covalent: Equal sharing of electrons Ionic: Electrons are transferred Increasing ionic character 1.7 Increasing polarity Covalent BondIonic Bond NonpolarPolar 2 nonmetals metal & nonmetal

5. Polar bonds Covalent bonds with unequal sharing of electrons. The atom with the higher electronegativity will attract the electrons more of the time and get a slight negative charge. The atom with the lower electronegativity will not have the electrons around it as much and get a slight positive charge.

6. Water is a polar molecule. Even though water is neutral, the oxygen attracts the electrons enough of the time that it gets a slight negative charge and the hydrogens are left with a slight positive charge.

7. Use the difference in the electronegativities to determine the bond type for each of the following: 1.H – Cl4. K – Br 2. N – O5. P - H 3. C – H6. Mg - I 0.0 3.3 F-F P-H 1.7 Covalent BondIonic Bond NonpolarPolar 2 nonmetals metal & nonmetal

8. The Bare Essentials of Polarity Read the comic and answer the following questions. 1.How does the comic define a polar molecule? 2.Interpret the picture on the bottom of page 1. Explain how the iceberg, penguins and polar bears represent trends in electronegativity. 3.What is the artist trying to represent when there are two polar bears arm wrestling together or two penguins arm wrestling together on page 2? 4.What three types of bonds are represented on page 3 of the comic book? What happens to the electrons in each type of bond? 5.What are two definitions of “dipole” given in the comic book? 6.Name 3 things that the picture of CO 2 on page 4 illustrates about the molecule. 7.Describe what you think is happening to the penguins in the illustration of water on page 4.

9. The Bare Essentials of Polarity Read the comic and answer the following questions. 1.How does the comic define a polar molecule? 2.Interpret the picture on the bottom of page 1. Explain how the iceberg, penguins and polar bears represent trends in electronegativity. 3.What is the artist trying to represent when there are two polar bears arm wrestling together or two penguins arm wrestling together on page 2? 4.What three types of bonds are represented on page 3 of the comic book? What happens to the electrons in each type of bond? 5.What are two definitions of “dipole” given in the comic book? 6.Name 3 things that the picture of CO 2 on page 4 illustrates about the molecule. 7.Describe what you think is happening to the penguins in the illustration of water on page 4.

10. The Bare Essentials of Polarity Read the comic and answer the following questions. 1.How does the comic define a polar molecule? 2.Interpret the picture on the bottom of page 1. Explain how the iceberg, penguins and polar bears represent trends in electronegativity. 3.What is the artist trying to represent when there are two polar bears arm wrestling together or two penguins arm wrestling together on page 2? 4.What three types of bonds are represented on page 3 of the comic book? What happens to the electrons in each type of bond? 5.What are two definitions of “dipole” given in the comic book? 6.Name 3 things that the picture of CO 2 on page 4 illustrates about the molecule. 7.Describe what you think is happening to the penguins in the illustration of water on page 4.

11. The Bare Essentials of Polarity Read the comic and answer the following questions. 1.How does the comic define a polar molecule? 2.Interpret the picture on the bottom of page 1. Explain how the iceberg, penguins and polar bears represent trends in electronegativity. 3.What is the artist trying to represent when there are two polar bears arm wrestling together or two penguins arm wrestling together on page 2? 4.What three types of bonds are represented on page 3 of the comic book? What happens to the electrons in each type of bond? 5.What are two definitions of “dipole” given in the comic book? 6.Name 3 things that the picture of CO 2 on page 4 illustrates about the molecule. 7.Describe what you think is happening to the penguins in the illustration of water on page 4.