Chapter 8:Ionic Compounds

P.211-233

Section 8.1

Forming Chemical Bonds

P.211-214

Objectives

• Define chemical bond

• Relate chemical bond formation to electron configuration

• Describe the formation of positive and negative ions

Key Terms

• Chemical bond

• Cation

• Anion

Review• Ionization energy refers to how easily an atom

loses an electron.

• Electronegativity refers to how much attraction an atom has for electrons.

• The presence of eight valence electrons is chemically stable (an octet).

• Elements tend to react to acquire that stable electron structure (of a noble gas).

Forming Chemical Bonds

• Chemical Bonds – The force that holds atoms together.

– An ionic bond is only one type of chemical bond

Ionic Compounds

• The attraction between a positive ion and negative ion

Positive Ions

• Cations

• Forms when an atom loses one or more valence electron(s) in order to attain a noble gas configuration.– Example:

• Sodium: 1s22s22p63s1

• Loses 1 electron to form Na+ = 1s22s22p63s0

• Neon: 1s22s22p6 (the same as Na+)

Positive ion question

– What noble gas configuration will a positive Mg ion have?

– What will the charge be on Mg?

Positive ion question

• Answers:– Neon– 2+

Negative ion– Anion– Forms when an atom gains one or more valence

electron(s) in order to attain a noble gas configuration.

– Example:• Fluorine: 1s22s22p5

• Gains 1 electron to form F- = 1s22s22p6

• Neon: 1s22s22p6

The D-Block• The transition metals in the d-block are less

predictable than metals and nonmetals.

• They tend to lose 2 or 3 electrons

• 2+ or 3+ charge

Homework

• P.214 #1-5

• P.236 #47-50, 60-66