Ionic/Covalent Compounds Characteristics

& Counting Atoms/Molecules

Ionic Compounds

• We already learned that ionic compounds are formed from 1 atom on the left and 1 atom on the right of the staircase on the Periodic Table getting together.

• Hundreds of compounds contain ionic bonds

Ionic compounds

• If ionic bonds occur between metals and oxygen, oxides form.

• Most other ionic compounds are called salts.

Ionic Compounds

• Many ionic compounds are binary (have 2 elements only)

• Binary compounds = 1 cation (positive ion) and 1 anion (negative ion)

• Cation = Loses electron• Anion = Gains electron

Example

• CaF2 = (Calcium = +2 charge ………………. (+2)

• (Fluoride = -1 charge …..-1 +-1 … (-2) Net: 0

Ionic compounds

• Form repeating patterns that form an ionic crystal….called a lattice crystal. (the cube)

• NaCl (Salt) is what shape under a microscope?

Ionic bonds

• Ionic bonds = Very strong…….hard to break….takes a lot of energy to break them.

• Ionic bonds = high melting points and high boiling points because it is hard to break the bonds and bonds must be broken to melt and to boil…….

Ionic Compounds

• In solid state….they are nonconductors of electricity…..because ions are fixed in solids and can’t move

• When dissolved into liquid…….electricity will go through them…..because ions are free to move……these liquids are called electrolytes

Counting Atoms and Molecules

• 2NaCl

• How many Na atoms?• How many Chlorine atoms?• How many NaCl compounds?

Counting Atoms and Molecules

• 2NaCl

Counting Atoms and Molecules

• 2NaCl

• How many NaCl compounds? 2 • How many Na atoms? • How many Chlorine atoms?

Counting Atoms and Molecules

• 2NaCl

• How many NaCl compounds? 2• How many Na atoms? 2• How many Chlorine atoms?

Counting Atoms and Molecules

• 2NaCl

• How many NaCl compounds? 2• How many Na atoms? 2• How many Chlorine atoms? 2

Guided Practice #1

• 3 CO2

• How many carbon atoms?• How many oxygen atoms?• How many molecules of CO2?

Guided Practice #1

• 3 CO2

• How many molecules of CO2? 3

• How many carbon atoms? • How many oxygen atoms?

Guided Practice #1

• 3 CO2

• How many molecules of CO2? 3

• How many carbon atoms? • How many oxygen atoms?

Guided Practice #1

• 3 CO2

• How many molecules of CO2? 3

• How many carbon atoms? 3• How many oxygen atoms?

Guided Practice #1

• 3 CO2

• How many molecules of CO2? 3

• How many carbon atoms? 3• How many oxygen atoms? 6

Guided Practice #2

• Ionic compounds have ____________ melting points and ____________ boiling points.

Guided Practice #2

• Ionic compounds have HIGH melting points and HIGH boiling points.

Guided Practice 3#

• 5 KBr

• How many molecules of KBr= • How many K atoms= • How many Br atoms =

Guided Practice #3

• 5 KBr

Guided Practice #3

• 5 KBr

• How many molecules of KBr= 5 • How many K atoms= • How many Br atoms =

Guided Practice #3

• 5 KBr

• How many molecules of KBr= 5 • How many K atoms= • How many Br atoms =

Guided Practice #3

• 5 KBr

• How many molecules of KBr= 5 • How many K atoms= 5 • How many Br atoms =

Guided Practice #3

• 5 KBr

• How many molecules of KBr= 5 • How many K atoms= 5 • How many Br atoms = 5

Guided Practice #4

• Oxides are formed when metals come together with _______________.

Guided Practice #4

• Oxides are formed when metals come together with Oxygen.

Independent Practice

• Now it is your turn…..feel free to ask any questions whenever you are confused.