Catalyst – September 5(6), 2010HOMEWORK OUT PLEASE!

Based on the octet rule, how many electrons will the following atoms need to gain or lose to be stable?? Write “gain” or “lose” and number of electrons.

1. Na2. Cl3. Pb4. Xe5. Ca

Today’s Agenda

Catalyst Homework Review Writing Ionic Formulas! Naming Ionic Compounds! Practice! Exit Question

Homework: Bond/Formula Worksheet!

Study for Quiz 3.1!

Today’s Objectives

SWBAT show the formation of ionic bonds.

SWBAT write formulas for balanced ionic compounds.

SWBAT name ionic compounds.

Yesterday’s Exit Question

1. List 3 characteristics of ionic compounds.

2. Which has a higher FIRST ionization energy: sodium (Na) or francium (Fr)?

Higher 3rd IE – B or Ca?

F

Mg

Higher 1st IE – F or Mg?

Test Prep Review

Which general trend is demonstrated by the Group 17 elements as they are considered in order from top to bottom on the Periodic Table? (1) a decrease in atomic radius (2) a decrease in electronegativity (3) an increase in first ionization energy (4) an increase in nonmetallic behavior

Test Prep Review

An atom of aluminum in the ground state and an atom of gallium in the ground state have the same (1) mass (2) electronegativity (3) total number of protons (4) total number of valence electrons

Let’s think about this…

What does lithium do to become stable?

What does chlorine do to become stable?

How do they come together???

Let’s think about this…

What does beryllium do to become stable?

What does oxygen do to become stable?

How do they come together???

Let’s think about this…

What does beryllium do to become stable?

What does chlorine do to become stable?

How do they come together???

Alright…

That process takes a long time…scientists aren’t going to do it every single time

WE HAVE A SHORCUT TO FIND WHAT IONIC COMPOUND WILL FORM!

Get ready for it…

Kris Kross Method!

Ca3As2

Ca2+As3-

Key Point #1: To write ionic formulas, write down the stable ions and cross the oxidation numbers (charges) to make them subscripts

Na1+Cl1-

NaClLi1+O2- Li2O

Use the charges:

Group 1 2 3 4 5 6 7 8Charge 1

+2+

3+

4-

3-

2-

1-

0

The two ionic charges must

balance to ZERO!!!

Or use the ionic cheat sheet to find the charges.

Remember! The two ionic charges must balance to

ZERO!!!

Kris Kross Method!

Ca3As

2

Ca2+As3-

Which charge ALWAYS comes first?POSITIVE!!!

Which type of element ALWAYS comes first?METAL!!!

K F Ba N Ga O Ca Cl K Si Co I

K1+F1- Ba N Ga O Ca Cl K Si Co I

KF Ba N Ga O Ca Cl K Si Co I

KF Ba2+N3- Ga O Ca Cl K Si Co I

KF Ba3N2 Ga O Ca Cl K Si Co I

KF Ba3N2 Ga3+O2- Ca Cl K Si Co I

KF Ba3N2 Ga2O3 Ca Cl K Si Co I

KF Ba3N2 Ga2O3 Ca2+Cl1- K Si Co I

KF Ba3N2 Ga2O3 CaCl2

K Si Co I

KF Ba3N2 Ga2O3 CaCl2

K1+Si4- Co I

KF Ba3N2 Ga2O3 CaCl2

K4Si Co I

K F Ba N Ga O Ca Cl K Si Co I

You don’t know about transition metals! So.. the problem must tell you the

number of electrons. Cobalt (II) means that Cobalt gives

up 2 electrons

K F Ba N Ga O Ca Cl K Si Co2+I1-

K F Ba N Ga O Ca Cl K Si CoI2

Polyatomics

3-

1 Phosphate Ion

PO4

3-

2 Phosphate Ions

(PO4)2

Calcium Phosphate

Ca2+ PO43-

3-

Ca2

+Ca2

+

3-

Ca2

+

6+

6-

For POLYATOMICS it gets a bit more complex

Pb4+SO42- Pb2(SO4)4

NH4 1+PO43- (NH4)3 PO4

You have a little memorizing to do…

You have to memorize the formula and charges for these polyatomic ions for the test…

And life

Naming Ionic Compounds

Formula forIonic Compound

Name forIonic Compound

NaCl Sodium chlorideCaCl2 Calcium chloride

KBr Potassium bromide

MgF2 ???

NaBr ???

Naming Ionic Compounds

Key Point #2: To name ionic compounds,

•Write full name of first element (metal).

•Second element ends in -ide.

•Ignore subscripts!

Naming Ionic Compounds

Draw a mental line between the

ions.Na+ Cl-

Naming Ionic Compounds

Binary Ionic Compound – an ionic compound

composed of two elements

Naming Ionic Compounds

CaCl2

Naming Ionic Compounds

CaCl2

Calcium Chloride

Naming Ionic Compounds

Al2O3

Naming Ionic Compounds

Al2O3

Aluminum Oxide

Naming Ionic Compounds

ZnO

Naming Ionic Compounds

ZnO

Zinc (II) Oxide

Naming Ionic Compounds

BaCO3

Barium

Naming Ionic Compounds

If the first element is +2, where

should we find the second?(Remember, charges must

balance!)

Naming Ionic CompoundsBaCO3

Barium

Naming Ionic CompoundsBaCO3

Barium Carbonate

Naming Ionic CompoundsAlPO4

Naming Ionic CompoundsAlPO4

Aluminum

Naming Ionic CompoundsAlPO4

Aluminum Phosphate

Naming Ionic CompoundsH2SO4

Naming Ionic CompoundsFeSO4

Naming Ionic CompoundsFeSO4

What do we do about transition

metals??

Naming Ionic CompoundsFeSO4

Sulfate

Naming Ionic CompoundsFeSO4

Since Sulfate is -2, Fe must be

+2

Naming Ionic CompoundsFeSO4

Iron(II) Sulfate

Naming Ionic CompoundsFeSO4

Iron(II) Sulfate or

Ferrous Sulfate

Exit Question

Write the formulas and names for the compounds that will form from the following elements.

1. Ga Cl2. K S

3. Mg2+ (PO4)3-

Exit Question

1. What is the formula for ammonium sulfate?

2. Write the formulas formed from the following atoms/ions:A) K OB) Na BrC) Mg S