Lesson 1:Class Starter What is the chemical symbol for silicon? How many electrons does silicon have? How many valence electrons does silicon have?

Chemical Bonding

3 Types of Bonds Ionic  An Ionic Bond is a chemical bond resulting from the TRANSFER of electrons from one bonding atom to another Between metals and nonmetals

3 Types of Bonds Covalent  A covalent bond is a chemical bond resulting from SHARING of electrons between 2 bonding atoms. Between nonmetals

3 Types of Bonds Metallic  A metallic bond occurs between metals. A metal consists of positive ions surrounded by a “sea” of mobile electrons.

Why Bond? Forming of a bond is like marriage…more stable. The breaking of a bond relates to a divorce. .. Less stable.

Octet Rule Rule that states that atoms tend to gain, lose, or share electrons so that each atom has full outermost energy level which is typically 8 electrons.

Valence electrons in ionic bonds 1 2 3 4 5 6 7 If an element has 3 or less valence electrons, it will lose them. If an element has 5 or more valence electrons, it will gain enough to fill outer level.

Valence electrons in ionic bonds 1 2 3 4 5 6 7 If an element has 4 valence electrons, it can gain or lose valence electrons depending on what it “needs” to do.

Practice How many electrons do the following elements want? Carbon? Nitrogen? Lithium? C would like to N would like to Li would like to Gain or Lose 4 electrons Gain 3 electrons Lose 1 electrons

Ions When atoms gain or lose electrons, they are called ions.

Ions If an element loses electrons then it becomes positively-charged and is called a cation Metals are always the cation. It is very easy to lose these electrons and become positively charged.

Ions If an element gains electrons then it becomes negatively-charged and is called an anion Nonmetals are always the anion. It is very easy to gain enough electrons to fill the outer energy level and become negatively charged.

Formation of Sodium Ion Sodium Atom Sodium Ion 2, 8, 1 Will sodium gain or lose its valence e- ? Na+ LOSE 11 p+ 11 e- - 1 e- = 10 e- 1 +

Formation of Boron Ion 2, 3 Will boron gain or lose its valence e- ? Boron Atom Boron Ion 2, 3 Will boron gain or lose its valence e- ? B+3 LOSE 5 p+ 5 e- - 3 e- = 2 e- 3 +

Formation of Sulfur Ion Sulfur Atom Sulfur Ion 2, 8, 6 Will sulfur gain or lose its valence e- ? S-2 Gain 16 p+ 16 e- + 2 e- = 18 e- 2 -

Formation of Fluorine Ion Fluorine Atom Fluorine Ion 2, 7 Will fluorine gain or lose its valence e- ? F-1 Gain 9 p+ 9 e- + 1 e- = 10 e- 1 -

Ionic Bonding Na+1 F-1 NaF Occurs when two or more ions combine to form an electrically-neutral compound. Create a compound between sodium and fluorine. Na+1 F-1 NaF

Ionic Bonding Na+1 S-2 Na+1 Na+1 S-2 Na2S Create a compound between sodium and sulfur. Na+1 S-2 Na+1 Na+1 S-2 Na2S

Ionic Bonding Mg+2 Cl-1 Mg+2 Cl-1 Cl-1 MgCl2 Create a compound between Magnesium and Chlorine. Mg+2 Cl-1 Mg+2 Cl-1 Cl-1 MgCl2

Transition Metal Ions Cobalt Co+2 Mercury Hg+2 Iron (II) Fe+2 Nickel Ni+2 Iron (III) Fe+3 Tin Sn+2 Lead (II) Pb+2 Silver Ag+1 Lead (IV) Pb+4 Zinc Zn+2 Manganese Mn+2

Lesson 2: Class Starter Will bromine gain or lose electrons? How many? Will magnesium gain or lose electrons? How many? What “charge” will bromine obtain? What “charge” will magnesium obtain? Make a compound between bromine and magnesium.

Class Starter Will aluminum gain or lose electrons? How many? Will oxygen gain or lose electrons? How many? What “charge” will aluminum obtain? What “charge” will oxygen obtain? Make an ionic compound between aluminum and oxygen.

Class Starter Will boron gain or lose electrons? How many? Will carbon gain or lose electrons? How many? What “charge” will boron obtain? What “charge” will carbon obtain? Make an ionic compound between boron and carbon.

Naming Ionic Compounds Ionic compounds all have two-word names The first word in the name is the same as the name of the cation (positive ion) The second word in the name is the anion (negative ion) with the ending “-ide”. Ex. Chlorine  Chloride or Oxygen  Oxide

Practice Naming Ionic Compounds Sodium and Fluorine  Sodium and Sulfur  Magnesium and Chlorine  Sodium Fluoride Sodium Sulfide Magnesium Chloride

Polyatomic Ions There are some ions that are made up of more than one type of atom, these are called polyatomic ions.

Practice Naming Ionic Compounds Na2CO3 -- CaSO4 -- KBr -- NH4F -- Sodium Carbonate Calcium Sulfate Potassium Bromide Ammonium Fluoride