Ionic Compounds

Bonds

•Chemical bonds are __________ forces

•They act between atoms within a molecule

Why does bonding occur?

•Bonding occurs to maximize stability of the atoms involved.

•More stable = LOWER potential energy

Bond types• Dependent on the difference between the __________________ of the elements involved in bond▫Electronegativity

Ability of an atom to ________________ Highest found in _______________ _________ are not ranked

Bond Types (cont)

•To Determine Type▫Subtract the electronegativities▫If difference is

______ – bond is non-polar covalent ______- bond is polar covalent Greater than 1.67- ______

Bonding is all about the electrons!• Bond type tells us what will happen to the electron(s)

• Octet rule will give us an idea of how many electrons will be involved▫Have to look at __________________▫Remember most atoms are stable with

___▫Common exceptions

H, He, Li, and Be can be stable with 2 B is stable with 6 Elements with d orbitals (can have

more than 8)

Valence electrons

Ionic bonding• Ionic bonding involves the ______ of valence electrons.

• Creates _____▫Cation- + ion (___ electrons)▫Anion- - ion (____ electrons)

•Ions of opposite charges are attracted to each other (the attraction is the bond)

Na

F

Electron is transferred

Na F

Charges

Na F+1 -1

Atoms are attracted to each other

Na F+1 -1

And each have 8 valence electrons

Ionic Compounds

•Will often form a _____ structure

•Formulas give the ___________ number ratio between the ions

Formulas

•Elements in the compound are listed with the number of atoms of each type listed as ___________▫For example, NaCl

Has a ___ ratio of Na+ ions and Cl- ions▫CaI2

Has a ___ ratio of Ca+2 ions to I- ions

Formulas (cont.)

•More complex formulas can have parenthesis with a subscript on the outside

•The subscript on the outside applies to all elements ___ the parenthesis ▫For example, Al(NO3)3

Has __ Al atom ___ N Atoms And ___ O atoms

Binary Compounds

•Compounds only containing ___________ of elements▫For example

H20 FeI3

NaCl Ag2S CaBr2

Ionic Compounds: Binary

•Binary: Metal bonded with Nonmetal ▫Type 1- Metal comes from Group

___________

▫Type 2- Metal comes from Group _________ Transition metals are multivalent (can take

multiple charges) Except Ag (___), Cd (___), and Zn (___)- treat

these like type 1

Base Name

•_______ is named

•Anion is named, but ending is changed to _____

Binary Compounds: Type 1 • Compound made from a metal from group 1, 2, Al, Ag, Cd,

or Zn with a nonmetal (ionic bond)▫ For example: NaCl, BeF2, Al2O3, K2S

• Metal forms a cation▫ Group 1- ___▫ Group 2- ___▫ Al- ___▫ Ag- ___▫ Cd- ___▫ Zn- ___

• Nonmetal forms an anion▫ Sometimes Group 14- ____▫ Group 15- ____▫ Group 16-____▫ Group 17- ____

Creating Type 1 Formulas

•Steps1. Determine the charge of the ion that each

element will form2. Determine how many ions of each type

will be needed to make the overall charge of the compound zero (neutral)…put each number as subscripts after that element’s symbol

3. Make sure the formula is reduced to its simplest form

Creating Type 1 Formulas (cont)•For example,

▫What is the formula for a compound made of calcium and bromine?

Ca2+

Br-

Br-

Naming Type 1 Compounds

•Base Name ________▫Metal is named first▫Make sure to change the ending of the

anion to -ide

▫For example: NaCl is ___________ CaBr2 is ____________ Li2O is _____________

Binary Compounds: Type 2 • Compound made from a metal from group 3-12

(transition metals or multivalent metals) with a nonmetal (ionic bond)▫ For example: FeCl2, FeCl3, Cu2S3

• Metal forms a cation▫ Charges vary from element to element▫ Most of the transition elements can have several

different charges• Nonmetal forms an anion

▫ Sometimes Group 14- -4▫ Group 15- -3▫ Group 16- -2▫ Group 17- -1

Creating Type 2 Formulas

1. Determine the charge of the anion (the charge of metal will be given to you)

2. Determine how many ions of each type will be needed to make the overall charge of the compound zero (neutral)…put each number as subscripts after that element’s symbol

3. Make sure the formula is reduced to its simplest form

Creating Type 2 Formulas (cont)•For example,

▫What is the formula for a compound made of iron (+2) and chlorine?

Fe2+

Cl-

Cl-

Naming Type 2 Compounds• Base Name + Roman numeral for charge of

metal▫Metal is named first▫Make sure to change the ending of the anion to -ide▫After the name of the metal, the charge of the

metal needs to be put in Roman numerals in parenthesis (because we can’t just look up the charge on the periodic table)

▫For example FeCl2 is ______________ Fe2O3 is _____________ CrS is _______________

Other Ionic Compounds: Polyatomic Ions• Polyatomic ions- two or more atoms combined

that have an overall charge (form an ion)

2-

CO32-

+

NH4+

Polyatomic Names• 10 Polyatomic Names to memorize• Others can be built off of those names

▫Base is __________▫One less oxygen is ___________

• For example:▫NO3

- is ______________

▫NO2- is _____________

Compounds with Polyatomic Ions•Can be

▫Type 1 metal (groups 1, 2, Al, Ag, Cd, or Zn) cation bonded with a polyatomic anion For example: Mg(NO3)2, Cs2SO4, Ca(IO3)2

▫Type 2 metal (transition metal) cation bonded with a polyatomic anion For example: NiSO3, Fe2(CO3)3

▫Or, a polyatomic cation bonded with a nonmetal (treat like a type 1) NH4Cl, (NH4)2O

▫All of these are ionic bonds

Creating Formulas for Compounds with Polyatomic Ions1. Determine the charge of the cation and aniono Polyatomic ion- charto Type 1 metal and nonmetals- determine charge from

group # on periodic tableo Type 2 metals- charge will be given to you

2. Determine how many ions of each type will be needed to make the overall charge of the compound zero (neutral)…put each number as subscripts after that element’s or polyatomic ion’s symbol

o If a subscript is placed after a polyatomic ion, the ion should be put in parenthesis with the subscript after it.

3. Make sure the formula is reduced to its simplest form

Creating Formulas for Compounds with Polyatomic Ions (cont)•For example,

▫What is the formula for a compound made of potassium and the polyatomic ion hydroxide?

Creating Formulas for Compounds with Polyatomic Ions (cont)•For example,

▫What is the formula for a compound made of gold (+2) and the polyatomic ion phosphate?

Creating Formulas for Compounds with Polyatomic Ions (cont)•For example,

▫What is the formula for a compound made of the polyatomic ion ammonium and bromide?

Naming Compounds with Polyatomic Ions• Compounds with

▫ Type I metals and a polyatomic anion (base name without –ide) Same as before except polyatomic ion name is the

second name (do not change the ending to –ide) For example: LiC2H3O2 is lithium acetate

▫ Type II metals and a polyatomic anion (base name without –ide but with Roman numeral) Same as before except polyatomic ion name is the

second name (do not change the ending to –ide) For example: Sn(ClO3)2 is tin (II) chlorate

▫ A polyatomic cation and a nonmetal (base name) Polyatomic ion name comes first, the second name is

the name of the nonmetal with the ending changed to –ide For example: NH4F is ammonium fluoride