Lab Teams – Chem T 1AStation 1- Steven V, Max, Amulya, Kahdijah

Station 2- Chuck, Gabby, Tanay, Jas-Lynn

Station 3- Danyal, Sanya, Moe, Frances Station 4- Steven T, Julia, Jarar, Rahul, Elsu Station 5- Taran, Athul, Rohan, Ben

Station 6- Manasa, Russell, Trishi, Matt

Lab Teams - Chem T 2AStation 1- Manav, Hannah, Jaylend, Pooja

Station 2- Kenny, Fatumo, Ally, Jack

Station 3- Andrea, Abdul-Ahad, Amanda

Station 4- Kevin, Sam, Kailey

Station 5- Peter, Hussain, Anthony, Dhruv

Station 6- Janae, Jonathan, Samvit, Nidhi

Charges of Ions, Naming Ionic Compounds

Atoms have NO overall charge• Atoms are not charged, even though they are made up

of charged particles

• Atoms have an equal number of protons (positive charge) and electrons (neg. charge) whose charges exactly cancel.

• Ex: Helium (He)– 2 protons, 2 neutrons, 2 electrons

+2 0 -2 = 0 total charge

Why do atoms bond??

• Atoms bond to be more stable!!

• Atoms join to form bonds so that each atom has a full outermost energy level – by either sharing or transferring electrons

• What is the number of electrons that atoms want to have in their outermost shell?

Ionic Bonds•Ionic bonds are formed

between oppositelycharged ions.

Ionic bonds are formed by the transfer of electrons

•Ionic bonds exist between metal and non-metal and are called Ionic Compounds

Covalent Bonds•Covalent bonds are formed by the

sharing of electrons between atoms

Covalent Bonds exist between non-metals and are called molecular compounds

Atoms gain or lose electrons to become IONS

Copyright © by Holt, Rinehart and Winston. All rights reserved.

Some Atoms Form Ions•An ion is an atom or group of atoms that has lost or

gained one or more electrons and has a net negative or positive charge.• A lithium atom loses one electron to form a 1+ charged ion:

• A fluorine atom gains one electron to form a -1 charged ion:

Chapter menu

Resources

Formation of Ions

• Cation: an atom loses one or more electrons and becomes positively charged

Na – 1 electron Na+

• Anion: an atom gains one or more electrons and becomes negatively charged

Cl + 1 electron Cl-

+ +

When will an element form a cation? When will an element form an anion?• An element wants to be stable. A stable electron

arrangement is one with eight electrons in the valence (or outer) shell.

Barium = 2 valence e- = Ba2+ cation

Iodine = 7 valence e- =I- anion

What is the charge on the ions of the following elements? Hint: Use your Periodic Table!!

• Sodium• Magnesium• Fluorine• Oxygen• Cesium• Phosphorus• Aluminum

OK Cool, Now that we know that..

Writing and Naming Ionic Formulas

Copyright © by Holt, Rinehart and Winston. All rights reserved.

Objectives

•Name simple ionic compounds.

•Write chemical formulas for simple ionic compounds.

Chapter menu Resources

Copyright © by Holt, Rinehart and Winston. All rights reserved.

Chapter menu Resources

Writing Ionic FormulasWhat is the chemical formula for aluminum fluoride?

1.List the elemental symbols for each ion (with the cation first)

2. Write the charges as superscripts for each ion.

3.Criss-cross values of charges

4.Write the chemical formula, indicating with subscripts how many of each ion are needed to make a neutral compound.

What is the formula for the compound made of Ca2+ cations and Cl1- anions?

Total charges of possible formulas are shown:

CaCl: 1Ca2+ + 1 Cl1- (2+) + (1-) = 1+Ca2Cl: 2 Ca2+ + 1 Cl1- (2+) + (2+) + (1-) = 4+CaCl2: 1 Ca2+ + 2 Cl1- (2+) + (1-) + (1-) = 0

The only formula that is neutral is CaCl2

Use the crisscross method to find the formula of an ionic compound

1. Write the cation and anion symbols with ionic charges. For calcium chloride,Ca2+ Cl1-

2. Make the number in the positive charge into a subscript for the anion. Make the number in the negative charge into a subscript for the cation. Ignore the – and + signsCa2+ Cl1-

Ca 1 Cl 2 = CaCl2

3. If necessary, reduce the resulting formula to its smallest whole-number ratio. To do this, divide all subscripts by the largest common factor

What is the formula for the compound made of Mg2+ cations and Br1- anions?

What is the formula for the compound made of Al3+ cations and S2- anions?

Practice

• Write ionic formulas for the following ionic compounds:

• Lithium oxide• Beryllium chloride• Magnesium oxide• Sodium Chloride• Lithium Nitrate• Aluminum Sulfide

Naming Binary Ionic Compounds• There are two types of binary ionic compounds:

– Type I: Metal only forms one cation (not a transition metal)– Type 2: Metal can form two (or more) cations that have different charges

(transition metal)

• Naming Type I Binary Compounds– Name the cation first and the anion second– Replace the ending of the anion with –ide to it.

• Examples:– NaCl

• Sodium Chloride– CaO

• Calcium Oxide

– ZnCl2 • Zinc Chloride

Important!!

• Some metal atoms form ions with different charges under different conditions. To specify the charge for these ions, Roman numerals are used in parentheses after the name of the metal. These include: copper, lead, iron, mercury.

• Check your ion reference sheet!!

Naming Binary Ionic Compounds with Cations of Varying Charge

– Name the cation first – Write charge of cation as roman numeral in parentheses– Anion with the –ide ending

• Fe2O3

– Iron (III) Oxide• AuCl– Gold (1) Chloride

• CuBr2

• Copper (II) Bromide

Copyright © by Holt, Rinehart and Winston. All rights reserved.

Naming Binary Ionic Compounds – Ions of varying chargeSome cation names must show their charge.

• Iron can form two different cations. Fe2O3 is made of

Fe3+ ions, so it is named iron(III)oxide. FeO is made of Fe2+ ions, so it is named iron(II) oxide.

To determine the charge of a transition metal cation,look at the total charge of the compound.

• You can tell that the iron ion in Fe2O3 has a charge of 3+

because the total charge of the compound must be zero, and an oxide ion, O2–, has a a charge of 2–.Chapter menu Resources

Try these!

• CuCl• CuCl2

• PbF2

• PbF4

Write the Formula for Binary Ionic Compounds with Transition Metals

Iron (111) Sulfide

Tin (11) Chloride

Copper(1)Oxide

Tin (1V) Oxide

Tin(11) Oxide

Naming Tertiary Compounds

• Naming Tertiary Ionic Compounds– Name cation– Indicate the charge if cation has varying charges– Name the polyatomic ion

A polyatomic ion is a group of two or more atoms covalently bonded or metallically bonded together to function as a single ion (has a charge associated with it).

An example being the hydroxide ion, OH-. The oxygen and hydrogen are covalently bonded together, and function as a single anion with a 1- charge.

Polyatomic IonsBrO3

- bromate

IO3- iodate

CO2-2 carbonite

Naming Tertiary Ionic Compounds• Check if the cation requires that you show charge• Name cation• Name anion (polyatomic)

• Examples– Na2SO4

– Fe(NO3)3

– (NH4 )OH

– Cu(NO2)2

Writing Formulas for Tertiary Ionic Compounds

Potassium Hydroxide

Magnesium Sulfate

Iron (111) Nitrate

Zinc (11) Phosphate

CaBr2

SnO

Pb(CO3)2

WRITE THE CHEMICAL FORMULA

Don’t use parentheses unless necessary

Mercury (II) sulfide

Cobalt (III) nitrate

Magnesium phosphate

Tin (II) Nitride

Copper (I) Sulfide