Warmup – write out the answer• Identify these compounds as covalent or ionic

1. SiO2 is _____

2. FeS2 is _____

3. cobalt(III) chlorate is _______

4. H2O is _______

• An ionic bond is____a) metal cations attraction to free floating valence

electron cloud.

b) non-metal elements sharing their electrons to make an octet

c) the attraction between cations and anions

Objective 6.5

•To know the properties of covalent compounds.

•To be able to write names for covalent compounds

What is the objective for today?

A. to learn properties of covalent compounds

B. to learn how to name covalent compounds

C. to learn as little as possible

D. both A and B are correct

An Ionic bond is…..

A. metal cations attraction to free floating valence electron cloud.

B. non-metal elements sharing their electrons to make an octet

C. the attraction between cations and anions

Which of these compounds is ionically

bonded?A. Si3O2

B. FeS2

C. cobalt(III) chlorate

D. H2O

cobalt(III) chlorateWhere do you find the formula and charge for

‘chlorate’ A. From the list on the back of your

periodic table: ClO3 charge is -1.

B. it must be Cl8 for chlorine eight

C. Chlorate is Cl-

I. What is a Covalent Compound?

A covalent compound is a compound composed of molecules.

A molecule is a neutrally bonded group of atoms that act as a unit.

Some examples of covalent compounds:

H2O Water

NO2 nitrogen dioxide

Millions of the same molecules grouped together make up a covalent compound.

Unlike ionic compounds, covalent compounds are composed of only nonmetallic elements.

What elements are covalent compounds composed of?

A. metals only

B. non-metals only

C. metals and non-metals

D. cations and anions

Covalent (molecular) compounds:– Relatively low melting and boiling points– Exist as gas or liquids at room temperature– Poor conductors of electricity

Which is true about the properties of covalent

compounds?

[

A. form crystals at room temperature

B. relatively low melting point, usually gas or liquid at room temperature

C. poor conductors of electricity

D. good conductors of electricity

When more than one nonmetallic element combines, they can do so in more than one way.

CO CO2

These two covalent compounds are composed of the same two elements, but they have completely different chemical properties.

What problem does this present when trying to distinguish between these two compounds?

CO CO2

These two covalent compounds are composed of the same two elements, but they have completely different chemical properties.

What problem does is presented when trying to distinguish between these two compounds?

Naming them

Two covalent compounds: SO2 and SO3

Would you expect them have the same chemical properties?

A. Yes

B. No

What name would be given to CO and CO2 using the same naming rules for ionic compounds?

What name would be given to CO and CO2 using the same naming rules for ionic compounds?

Carbon Oxide

But which one gets to use this name?

Obviously, a new naming system is needed for covalent compounds.

Obviously, a new naming system is needed for covalent compounds.

When naming covalent compounds, prefixes are used to distinguish between different compounds.

These prefixes indicate the number of atoms of each element used to compose a particular molecule.

Prefix Number

Mono- 1

Di- 2

Tri- 3

Tetra- 4

Penta- 5

Hexa- 6

Hepta- 7

Octa- 8

Nona- 9

Deca- 10

• What name would you now give to CO and CO2 using prefixes?

CO

CO2

• What name would you now give to CO and CO2 using prefixes?

CO Carbon Monoxide

CO2

• What name would you now give to CO and CO2 using prefixes?

CO Carbon Monoxide

CO2 Carbon Dioxide

1.Usually, if there is only one of the first element, the prefix mono- is omitted.

1.Usually, if there is only one of the first element, the prefix mono- is omitted.

2.The names of all covalent binary compounds end with –ide.

1.Usually, if there is only one of the first element, the prefix mono- is omitted.

2.The names of all molecular binary compounds end with –ide.

3.The vowel at the end of the prefix is sometimes dropped when the name of the element also begins with a vowel.

• Name the following covalent compounds.

1.SF2

2.PCl3

3.CCl4

4.Cl2O8

• Name the following covalent compounds.

1.SF2 Sulfur Difluoride

2.PCl3

3.CCl4

4.Cl2O8

• Name the following covalent compounds.

1.SF2 Sulfur Difluoride

2.PCl3 Phosphorus Trichloride

3.CCl4

4.Cl2O8

• Name the following covalent compounds.

1.SF2 Sulfur Difluoride

2.PCl3 Phosphorus Trichloride

3.CCl4 Carbon Tetrachloride

4.Cl2O8

• Name the following covalent compounds.

1.SF2 Sulfur Difluoride

2.PCl3 Phosphorus Trichloride

3.CCl4 Carbon Tetrachloride

4.Cl2O8 Dichlorine Octoxide

• Write the chemical formula using the following compound names.

5.Nitrogen triodide

6.Diselenium dichloride

7.Dinitrogen tetroxide

8.Sulfur trioxide

• Write the chemical formula using the following compound names.

5.Nitrogen triodide NI3

6.Diselenium dichloride

7.Dinitrogen tetroxide

8.Sulfur trioxide

• Write the chemical formula using the following compound names.

5.Nitrogen triodide NI3

6.Diselenium dichloride Se2Cl2

7.Dinitrogen tetroxide

8.Sulfur trioxide

• Write the chemical formula using the following compound names.

5.Nitrogen triodide NI3

6.Diselenium dichloride Se2Cl2

7.Dinitrogen tetroxide N2O4

8.Sulfur trioxide

• Write the chemical formula using the following compound names.

5.Nitrogen triodide NI3

6.Diselenium dichloride Se2Cl2

7.Dinitrogen tetroxide N2O4

8.Sulfur trioxide SO3