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1. Define electronegativity.

a measure of the ability of an atom in a chemical compound to attract electrons.

2. On the periodic table, where are the LEAST/MOST electronegative elements found?

Least-Bottom left Most-Top right

What are the rules for writing and naming stable ionic formulas?

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Chemical Bonding Vocabulary (Ch. 7 & 8)

1. Chemical formula

2. Ionic bonds

3. Ionic compounds

4. Metallic bonds

5. Octet rule

6. Valence electrons

7. Covalent bond

8. Diatomic molecule

9. Double covalent bond

10.Hydrogen bond

11.Molecular formula

12.Polar bond

13.Polyatomic ion

14.Single covalent bond

15.Triple covalent bond

Word Definition My Own Words Pic. Or Ex.

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CHEMICAL BONDING

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Chemical Compounds • Atoms of elements

are not chemically stable until they have 8 valence electrons (octet rule).

• Atoms gain, lose, or share electrons with other atoms to become chemically stable (8 valence electrons)

• The action taken by the electrons determine the type of bond formed

– Transferred ionic bond

–Shared covalent bond

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Introduction to Chemical Bonds

TWO basic forms of bonding:

• Ionic—transfer of 1 or more electrons from one atom to another (one loses, the other gains) forming oppositely charged ions that attract one another

• Covalent—some valence electrons shared between atoms

Most bonds are somewhere in between ionic and covalent.

6 The type of bond can usually be calculated by finding the difference in electronegativity of

the two atoms that are going together.

7 Electronegativity Difference

• If the difference in electronegativities is between:

– 1.7 to 4.0: Ionic

– 0.0 to 1.7: Covalent

Example: NaCl

Na = 0.9, Cl = 3.0

Difference is 2.1, so

this is an ionic bond!

Ionic Compounds • Ionic bonds form from the attractions between

oppositely charged ions.

• Metal + Nonmetal

– Metals tend to lose electrons to become positively

charged (cations)

– Nonmetals tend to gain electrons to become

negatively charged (anions)

QR Code Activity-Example

F K

Dot Diagrams

(show valence electrons)

F K +

_

QR Code Activity-Example

The ionic bond is the

attraction

between the positive K+ ion

and the negative F- ion

KF Put the symbols together and you

have the chemical formula

QR Code Activity-Example

Naming Ionic Compounds

• For the first element, use the full element name

– Potassium

• For the second element, change the ending to “-ide”

– Fluoride

KF

Potassium Fluoride

LABEL YOUR PERIODIC TABLE:

Determine the chemical formulas by

balancing the charges. Bonding pair Cation Anion Balance Charges Formula Name

Sodium and

Chlorine

Calcium and

Fluorine

Aluminum

and Oxygen

Special Ions

Transition Metals

• Can have more than one charge

– Ex: Cu+ and Cu2+

– Ex: Fe2+ and Fe3+

• Use a Roman Numeral in the name to show the CHARGE

– copper(I) and copper(II)

– iron(II) and iron(III)

Transition metals • Use a roman numeral to indicate the charge of the

metal for all metals other than Groups 1 & 2 and

Aluminum.

• Example: Copper & Oxygen

Cu +1 O

Cu +2

O

Cu +3 O

QR Codes!

Chemistry CAT Joke

1. What is the name for NaCl?

• A. sodium chloride B. sodium chlorine C. sodium I chloride

2. What is the correct formula for iron

(III) chloride?

• A. FeCl B. Fe3Cl C. FeCl3

3. What is the correct formula for Al+3

and Cl-1?

• A. Cl3Al B. AlCl C. AlCl3

4. What is the name for CaF2?

• A. calcium fluoride B. calcium II fluorine C. calcium II fluoride

5. What is the correct formula for

compound formed when a sodium ion

combines with a fluoride ion? • A. NaF2 B. NaF C. Na2F

6. What is the correct formula for

copper (II) chloride?

• A. CuCl B. Cu2Cl C. CuCl2

7. What is the correct formula for

calcium oxide ?

• A. CaO2 B. CaO C. Ca2O

8. What is the name for MgS?

A. magnesium II sulfide B. magnesium sulfur C. magnesium sulfide

9. What is the correct formula for silver (I)

chloride?

• A. SiCl B. AgCl C. AgCl3

10. What is the formula formed by a

potassium ion and a sulfur ion?

• A. K2S B. KS C. KS2

11. What is the compound formed from

Ca +2 and F-1?

• A. calcium fluoride B. calcium II fluorine C. calcium II

fluoride

12. What is the formula formed by Li +1

and O-2?

• A. Li2O B. LiO C. LiO2

Bell Ringer:

1. Define electronegativity.

a measure of the ability of an atom in a chemical compound to attract electrons.

2. On the periodic table, where are the LEAST/MOST electronegative elements found?

Least-Bottom left Most-Top right

EQ: What are the rules for writing and naming stable ionic

formulas?

The positive and negative charges must be balanced.

Change the ending of the nonmetal’s name to “-ide”.

1. What is an ion?

An atom that has gained or lost electrons

2. Why do atoms become ions?

To become more stable (by having a full outer

energy level).

Compounds

Is the first element

a metal?

Yes

It’s Ionic!

Metals:

Group I

or II, B

or Al

Metals:

Transition

and all

others

Polyatomic

ions

No, the first

element is not

a metal.

Is H is the

positive ion? No

Acidic

Compound Covalent

Compound

Special Ions-Polyatomic

• A tightly bound group of atoms that act as a unit but have a charge

• Examples: (OH- ) hydroxide ion

Ca

(SO42-) sulfate ion

Na

(SO32-) sulfite ion

Al

(NH4+) ammonium ion

O

Quick Tips: Shortcuts to Chemical Formulas

• Oxidation Number: Shows the charge of an ion

• Write the oxidation numbers across the top of

your periodic table

Mg2+

1+ 2+ 3+ 4+/- 3- 2- 1-

Quick Tips: Shortcuts to Chemical Formulas

Quick Tips: A Shortcuts to Chemical Formulas

1. Use the periodic table to determine the oxidation

number (charge) for each ion involved.

2. Criss-cross the oxidation numbers to become the

subscripts.

3. Reduce if necessary.

Li1+ O2- Li2O Lithium oxide

Use your reference sheet to write the correct formula for

ammonium sulfate.

(NH4)2SO4

How do you name ionic formulas with:

-transition metals

-polyatomic ions Use a roman numeral to indicate the

charge of the metal

Use the polyatomic name without any

changes

Use your reference sheet to write the correct formula for

Copper II Nitrate.

Cu(NO3)2

The objective for any ionic compound is to have a net

charge of ________. Zero

The positive and

negative charges

should cancel out.

Review

• Make a compound with the following ions

• Li +1 and O -2

• NH4 +1 and S -2

• Zn +2 and SO4 -2

Review

• Write the formula for the following compounds

• Barium nitrite

• Potassium oxide

• Iron (III) sulfide

Review

• Write the name for the following compounds

• CaCl2

• Cr2S3

• Al2(CrO4)3