Ionic BondingIonic BondingNaming and Naming and

formula writingformula writingMrs. Kay & Ms. ClearyMrs. Kay & Ms. Cleary

Chemistry 11Chemistry 11Read pages 158-168Read pages 158-168

RecallRecall Atoms of different Atoms of different

elements have elements have different numbers of different numbers of electronselectrons

Each shell is filled up Each shell is filled up before electrons move before electrons move to the next shell found to the next shell found further away from the further away from the nucleusnucleus

Ex: Sodium has 2 e- on Ex: Sodium has 2 e- on the 1the 1stst energy level, 8 energy level, 8 e- on the 2e- on the 2ndnd energy energy level, and 1 e- on the level, and 1 e- on the 33rdrd energy level. energy level.

Sodium has 1 valence electron

Valence electronsValence electrons Period numberPeriod number indicates the indicates the

number of electron shellsnumber of electron shells Group number Group number indicates the indicates the

number of valence electrons (look at number of valence electrons (look at the second digit of the group the second digit of the group number)number)

Trends:Trends: Elements of the Elements of the

same groupsame group have have similar chemical similar chemical propertiesproperties because because they have the same they have the same number of electrons number of electrons in their outer shell in their outer shell or valence shellor valence shell

Group 1 metalsGroup 1 metals reacting with waterreacting with water

Reasons for reactionsReasons for reactions Group 18, the noble gases are the most Group 18, the noble gases are the most

stable of elements because their stable of elements because their valence shell is full with electronsvalence shell is full with electrons

Less energy required to support the Less energy required to support the atomatom

Other atoms react in attempt to achieve Other atoms react in attempt to achieve nobel gas configuration, same number nobel gas configuration, same number of valence electrons as a noble gas.of valence electrons as a noble gas.

Lewis Dot structuresLewis Dot structures Visual representation of an element and Visual representation of an element and onlyonly its its

valence electronsvalence electrons sodium, Na has 1 valence so it has 1 dot sodium, Na has 1 valence so it has 1 dot

representing that electron. (group 1)representing that electron. (group 1) Chlorine, Cl has 7 electrons. (group 17)Chlorine, Cl has 7 electrons. (group 17) Electrons get placed up along 4 sides of the Electrons get placed up along 4 sides of the

element before they double up!element before they double up!

Ionic BondingIonic Bonding attraction between oppositely charged ions formed attraction between oppositely charged ions formed

when metallic ions (+) transfer electron(s) to when metallic ions (+) transfer electron(s) to nonmetallic ions (-)nonmetallic ions (-)

Difference of electronegativity greater than 1.7Difference of electronegativity greater than 1.7 Ex: NaCl Ex: NaCl

Not always 1:1 ratio, sometimes need to Not always 1:1 ratio, sometimes need to use subscript to show the number of use subscript to show the number of atomsatoms

Ex:Ex: CaCl CaCl2 2 The 2 is a subscript, it shows The 2 is a subscript, it shows that 2 atoms of chlorine bond with one that 2 atoms of chlorine bond with one atom of calcium.atom of calcium.

Zero Sum Rule:Zero Sum Rule: the charges need to add the charges need to add up to up to zerozero

Naming Ionic Naming Ionic CompoundsCompounds

Simple or Binary Ionic Simple or Binary Ionic Compounds (Formula to Compounds (Formula to

Name)Name) KBrKBr Name the (cation) metal firstName the (cation) metal first

PotassiumPotassium Name the root of the (anion) non-Name the root of the (anion) non-

metal, change the (suffix) end to –idemetal, change the (suffix) end to –ide Bromine becomes bromBromine becomes bromideide

Put together: Put together: Potassium bromidePotassium bromide

PracticePractice NaNa22OO

Name the metal:

Sodium

Name the non-metal:

Oxide

Put them together to get: Sodium Oxide.• It takes two Na+ to combine with one O2- to observe the Zero Sum Rule!

Simple or Binary Ionic Simple or Binary Ionic Compounds (Name to Compounds (Name to

Formula)Formula) To write the formula from a name To write the formula from a name

first you must look at the charges.first you must look at the charges. Remember ionic compounds are Remember ionic compounds are

made up of cations and anions made up of cations and anions (oppositly charged ions) but together (oppositly charged ions) but together the compound has no charge- the the compound has no charge- the charges balance each other out.charges balance each other out.

““Cross-over Method”Cross-over Method” This is a method used to make sure your This is a method used to make sure your

compound is balanced. compound is balanced. Write the formulas of the ions beside each Write the formulas of the ions beside each

other, then cross the number of the charge other, then cross the number of the charge of the cation so that it becomes the of the cation so that it becomes the subscript of the anion. Then cross over the subscript of the anion. Then cross over the number of the charge on the anion so that it number of the charge on the anion so that it becomes the subscript of the cation.becomes the subscript of the cation.

MgMg2+2+ ClCl1-1-

MgClMgCl22

Simple or Binary Ionic Simple or Binary Ionic Compounds (Name to Compounds (Name to

Formula)Formula) If you’re given the name, can you If you’re given the name, can you write the formula?write the formula? Strontium nitrideStrontium nitride Strontium is SrStrontium is Sr2+2+

Nitride is NNitride is N3-3-

We must combine them to be equal to We must combine them to be equal to zerozero Need 3 SrNeed 3 Sr2+ 2+ to combine with 2 Nto combine with 2 N3-3-

Answer is SrAnswer is Sr33NN22

Multivalent Ionic Multivalent Ionic bondingbonding

Whenever the periodic table of ions has a Whenever the periodic table of ions has a split cell, we must choose or indicate which split cell, we must choose or indicate which charge we are referring to in the chemical charge we are referring to in the chemical equation.equation. Look at Iron, the charge on Fe is written as a Look at Iron, the charge on Fe is written as a

roman numeral between the cation and the roman numeral between the cation and the anion.anion.

There is an option of FeThere is an option of Fe2+2+ and Fe and Fe3+3+

FeO would be called Iron (II) oxideFeO would be called Iron (II) oxide It takes FeIt takes Fe2+2+ to balance out charges with O to balance out charges with O2-2-

We indicate the optional charge with roman We indicate the optional charge with roman numerals; 2= II, 3=III, 4=IV and so onnumerals; 2= II, 3=III, 4=IV and so on

Practice namingPractice naming1.1. FeClFeCl22

2.2. MnOMnO3.3. FeFe22OO33

4.4. TiOTiO22

1. Iron (II) chloride2.Manganese (II)

oxide3.Iron (III) oxide4.Titanium (IV)

oxide

Polyatomic ionsPolyatomic ions Ions that are made of multiple atoms Ions that are made of multiple atoms

covalently bonded together.covalently bonded together. We treat them like a We treat them like a unit or packageunit or package When we need When we need more than onemore than one, must , must

be put inbe put in brackets!! brackets!! Example: sulphate, SOExample: sulphate, SO442-2-

Aluminum sulphate = AlAluminum sulphate = Al22(SO(SO44))33 Because is AlBecause is Al3+3+ and and SOSO442- 2- must combine must combine

to to ZeroZero

PracticePractice1.1. NaOHNaOH2.2. KK33POPO44

3.3. CsMnOCsMnO44

4.4. Ca(HCOCa(HCO33))22

5.5. Cu(NOCu(NO33))22

1.Sodium hydroxide2.Potassium phosphate3.Cesium permanganate4.Calcium hydrogen carbonate5.Copper (II) nitrate

Homework:Homework:1.1. Don’t forget to read over the Don’t forget to read over the

textbook pages for furhter textbook pages for furhter understandingunderstanding

2.2. Work on handouts to continue Work on handouts to continue practice with naming and proper practice with naming and proper formula writing (IUPAC = formula writing (IUPAC = international naming method, what international naming method, what we learned)we learned)

Test what you know Test what you know here:here:

http://science.widener.edu/svb/tutorial/namingcsn7.html