NOMENCLATURE IONIC BONDING

Thursday - Day 3 Notes

VIDEO CLIP ON HOW ATOMS BOND: IONIC COMPOUNDS

Click the link below to watch the video:

http://www.nbclearn.com/portal/site/learn/chemistry-now/how-atoms-bond

Quick Review

_Ions_____ - atoms that have lost or gained one or more electrons. __cation___ – positively charged ion _____anion___ – negatively charged ion The charge on the ion is known as the

___oxidation number____ __Polyatomic ion____ – ion consisting of

two or more atoms

Practice - write the ion with the charge for the following elements

* Li * Ca * H

* Be * Si * K

* Al * S * O

* Na * Fr * N

* F * Cl * P

+

2+

3+

+

-

2+ +

+-4 +

+ 3-

2-

2-

- 3-

NOTES #2: Binary Ionic Chemical Names and Formulas

Ionic bonds are formed between a

metal and a nonmetal OR

cation + anion. The bond involves the transfer of electrons from

the metal to the nonmetal. The electron is transferred from the cation to the

anion so that both atoms have a complete valence shell (usually 8 electrons in valance).

The overall charge of ionic compounds must equal

zero.

NamingIonic Compounds

* First name the cation and then the anion. (metal) (nonmetal)

* Change the ending of the anion to –ide.Example:

•MgCl2 magnesium chloride

•Li2S _________________________Lithium sulfide

Practice

MgO _________________________

K3P ________________________ CsCl ________________________ Ba3N2 ________________________

Magnesium oxide

Potassium phosphide

Cesium chloride

Barium nitride

DRAWING Lewis Dot Structures for Ionic Compounds

• The overall charge on the compound must equal zero, that is, the number of electrons lost by one atom must equal the number of electrons gained by the other atom.

• The Lewis Structure (electron dot diagram) of each ion is used to construct the Lewis Structure (electron dot diagram) for the ionic compound.

The Lewis Dot structures show the location of the valence electrons after the electrons have been transferred.Examples: Lithium fluoride

• Lithium atom loses one electron to form the cation Li+• Fluorine atom gains one electron to form the anion F- • Lithium fluoride compound can be represented as

Remember the Octet rule….

DRAWING Lewis Dot Structures for Ionic Compounds

Draw the Lewis structure of Lithium oxide. What would be the chemical formula for this compound?

Writing Formulas for Binary Ionic Compounds

When given two ions, __________________ the charges and make them the ___________________.

Do NOT keep the +/- signs _______________ subscripts if possible

This means we must reduce the subscripts if they have a common denominator. 

Example: Ca4F8

Balancesubscripts

Reduce

CaF2

Writing Formulas for Binary Ionic Compounds

Ex:a. Na+1 + Cl-1 NaCl (+1 + -1 = 0)

b. Mg+2 + O-2 MgO * (+2 + -2 = 0)

* Don’t write this Mg2O2 because it must be reduced.

**Sum of charges must equal zero.

A. Using Balanced charges Method: B. Using the Crisscross method:

Example: Li+1 O-2

Now, let’s use the name to write the chemical formula Name cation anion formula Lewis Dot Structure

Lithium oxide _______ _______ _____________Li+1 O-2 Li2O

Li+1

Important Facts about Ionic Compounds

• We use subscripts to represent the number of each ion.

Al2O3

2 Aluminum Ions and 3 Oxide Ions

A. Using Balanced charges Method: B. Using the Crisscross method:

Magnesium phosphide ______ _______ ____________

Name cation anion formula Lewis Dot Structure

Mg2+ and P3-

Mg2+

Mg2+

P3-

6+ 6- = 0

Mg2+ and P3-

Mg 3 S 2

Mg2+ P3- Mg3P2

For example 2…Change it from Magnesium sulfide to Magnesium phosphide

Homework: Page 9

For added help: watch this video

And use your periodic table!!!!

Notes 3: Binary Ionic Compounds with Transition Metals (Multivalent cations)

Multivalent Cations are found mostly in the group B elements. (the middle of the periodic table)

These elements are also known as the Transition metals.

If your cation is a transition metal, then you must specify the charge with a Roman numeral.

Example: Iron (III) Sulfide

Just like the compounds we looked at yesterday, the sum of charges must equal zero . and we can still use the Criss-cross method when writing the chemical formula.

Roman Numer

al

Charge

I +1II +2III +3IV +4V +5VI +6VII +7VIII +8

Writing & Naming Formulas with Roman Numerals Practice

Cu+ S2- Cu2S

Mn2+ O2- MnO

Sn4+ F- SnF4

I-Pb2+Lead II iodide

O2-Fe3+Iron III oxide

Pb4+Lead IV oxide

P3-Co3+Cobalt III phosphide

Naming Ionic Compounds with Roman Numerals

If there is a transition metal (B group element) present in the formula, you will need to include a roman numeral when you name the compound.

So, which metals DO NOT require a roman numeral?

Al3+, Zn2+, Cd2+ and Ag+

Writing Multivalent Compounds HOMEWORK

Complete page 11REMEMBER: How can you determine the charge or roman numeral?

You will have to work backwards.

And

Roman Numeral = Charge of the Metal

Polyatomic Ions

A polyatomic ion are groups of atoms that behave as one unit. They are treated like single ions in formulas, but use

parenthesis when more than one is used in a formula. NEVER change name or look of polyatomic. If you change the

subscripts for any part of the polyatomic, then it is no longer that same polyatomic ion.

Otherwise….use all the same rules for naming and writing compounds as with any other Binary Ionic compound.

EX: NH4+ is not the same as NH+

CO32- is not the same as CO2

2- or CO2-

Polyatomic Ion Practice

Formula Name

Al+3 CO3 -2

Ca+2 NO3 -1

K+1 ClO3 -1

Al2(CO3)3 Aluminum carbonate

Ca(NO3)2 Calcium nitrate

KClO3Potassium chlorate

Question: How would potassium chlorite be different?

K+1 ClO2 -1 KClO2

Name the following compounds

Ba(OH)2

CaSO4

(NH4)3P

Barium hydroxide

Calcium sulfate

Ammonium phosphide

Write the formula for the following compounds:

cation anion formula

Strontium phosphate ________ _________ ______________

Lithium acetate ________ _________ ______________

Sodium sulfate _________ _________ ______________

Sr2+

Formula Writing for Compounds

Tips for SuccessBefore writing any formula,

Identify the type of compound.Ionic Metal and a Nonmetal or PAIMolecular Only Nonmetals

For all ionic compounds, circle polyatomic ions.

Examples

iron(III) nitrate Fe(NO3)3

carbon tetrachloride CCl4sodium oxide Na2Obarium hydroxide Ba(OH)2

dinitrogen trioxide N2O3

ammonium carbonate(NH4)2CO3

cobalt(III) nitrite Co(NO2)3

I

I

I

M

I

I

M

Naming Ionic Compounds with Polyatomic Ions

When you name a compound with a polyatomic ion, the polyatomic ion keeps its name.

It is easy to identify a compound with a polyatomic ion because it will have more than 2 elements (more than 2 capital letters).

Tips for Success

Before naming ANY compound, Determine the type of compound. If the compound is molecular, remember use prefixes.

If the compound is ionic, answer the following questions.Does the metal need a roman numeral?

Does the compound have a polyatomic ion?

Examples

NaHCO3sodium hydrogen carbonate (NH4)2O ammonium oxide FeSO4 iron(II) sulfate AgC2H3O2 silver acetate Ni(NO3)2 nickel(II) nitrate ClO chlorine monoxide AuClO3 gold(I) chlorate

I

I

II

I

M

I

Monday Bell Ringer

Which of the following compounds represent trichlorine hexoxide? A. Cl3O6

B. ClO3

C. O3Cl6 Which of the following compounds

represent manganese (III) oxide? A. MgO B. Mn2O3

C. Mg2O3

Properties of Acids

CorrosiveSour TasteReact with Metals to Produce Hydrogen Gas (H+)

pH less than 7Can conduct electricityContain H+ ionsGenerally found as (aq) or aqueous

Binary Acids

Binary acids are made up of HYDROGEN + ANOTHER ELEMENT. Example: HCl (hydrogen + chlorine)

Example: H2S (hydrogen + sulfur)

Naming Binary Acids:

1. Prefix: hydro-

2. Element Name

3. –ic

4. Last word: “acid”

Ie: hydroelementic acid

In Class Examples: Naming Binary Acids

HCl hydrochloric acid

HF hydrofluoric acid

HBr hydrobromic acid

Ternary Acids

These acids contain a POLYATOMIC ION.

Also called oxy-acids.Example: H2SO3 = sulfurous acid

Naming Ternary Acids

1. Name the polyatomic ion. 2. Change PAI ending in –ate to –ic.

Example: sulfate sulfuric phosphate phosphoric

3. Change PAI ending in –ite to –ous. Example: sulfite sulfurous

phosphite phosphorous 4. Last word is “acid”.

In Class Examples of Naming Ternary Acids:

H2 SO4 sulfuric acid

H2 CO3 carbonic acid

HNO2 nitrous acid

H3PO4 phosphoric acid

Writing Acid Formulas

You do not have notes on this- we will practice in a minute!

Always begins with Hydrogen! Hydrogen = H+

You will then follow the same process as you would an IONIC compound! Example: hydrochloric acid = H+ and Cl- = HCl Example: sulfuric acid = H+ and SO4

2- = H2SO4

Writing Acid Formulas:

Tips:

1. Your first element is ALWAYS H+

2. Identify if it is a BINARY acid or TERNARY acid.

- begins with hydro- and ends in –ic? (1 element!)

- no hydro- prefix, or ends in –ous? (PAI!)

STOP: IN CLASS PRACTICE

I’ll make a SMART board notebook, you will probably want to do it on the overhead.

Exit Ticket will be the page in the notes titled “In Class Practice for Nomenclature of Acids.”

Darla just emailed out a homework that I’ll probably use!

Writing Formulas for Acids

Remember your patterns. Hydro-ic acid No oxygen X-ic acid -ate polyatomic ion X-ous acid - ite polyatomic ion

The positive ion is always H+.The sum of the charges of the ions must add up to zero.

Examples

hydroselenic acid H2Se

phosphoric acid H3PO4

nitrous acid HNO2

sulfurous acid H2SO3

dichromic acid H2Cr2O7

Keys to Success

Before naming ANY compound, Identify the type of compound.

Molecular? Ionic? Acid? If it is molecular, remember to use your prefixes.

If it is ionic, ask yourself.Does the metal need a roman numeral?Does it contain a polyatomic ion?

If it is an acid, which pattern does it follow?

Mixing It Up!

H2CrO4 chromic acid Na2SO3 sodium sulfite HF hydrofluoric acid P5O10 pentaphosphorus

decoxide Fe(C2H3O2)2 iron(II) acetate ZnCl2 zinc chloride H3PO3 phosphorous acid

A

I

A

MI

I

A

Keys to Success

Before writing the formula for ANY compound, Identify the type of compound.

Molecular? Ionic? Acid? If it is ionic, does it contain a polyatomic ion? If it is an acid, which pattern does it follow?No Oxygen?-ATE Polyatomic Ion?-ITE Polyatomic Ion?

Examples

barium phosphate Ba3(PO4)2

bromic acid HBrO3

ammonium dichromate (NH4)2 Cr2O7

iron(III) sulfide Fe2S3

dichlorine heptachloride Cl2O7

hydrosulfuric acid H2S

gold(III) chlorate Au(ClO3)3

I

A

I

I

M

A

I

-ate

No O

PUZZLE PIECE ACTIVITY ON WRITING FORMULAS FOR IONIC COMPOUNDS

•Work in pairs to assemble the various compounds.•Let’s try the first one together.• What is the compound formed between Mg and

F?Mg2+

Magnesium

F-

fluorideF-

fluoride

A perfectly assembled compound should be a square or a rectangle.

MetalMetal’sCharge

Nonmetal

Nonmetal’s Charge

Picture of Puzzle Pieces

Formula NameSum of Charges

Mg F+2 -1 MgF2magnesium

fluoride0