Objectives 1.Name and write the symbols for common anions,
cations, and polyatomic ions. 2.Determine the formula of an ionic
compound between any two given ions. 3.Name ionic compounds, given
their formulas. 4.Correctly use Roman numerals when naming
compounds containing transition metals with more than one oxidation
number. 5.Write formulas for ionic compounds, given their names.
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Slide 3
Naming and Writing Formulas for Ionic Compounds In forming a
chemical compound, an atom can gain, lose or share one or more
valence electrons. Back to main menu
Slide 4
Positive Ions A cation is an atom or group of atoms with a
positive charge. A cation has fewer electrons than a neutral atom
of the element. Back to main menu
Slide 5
Symbols of Ions for Cations The metals in groups 1, 2 and 13
lose electrons when they form ions. Group 1 forms +1 ions. Group 2
forms +2 ions Group 13 forms +3 ions. Back to main menu
Slide 6
Naming and Writing Symbols for Cations Back to main menu
ElementSymbol of IonName of Ion Calcium Sodium Aluminum Ca 2+
Calcium ion Na + Sodium ion Al 3+ Aluminum ion
Slide 7
Metals with More than One Common Oxidation Number The metals in
groups 3-12 are called transition metals. They often have more than
one common oxidation number (ionic charge). Back to main menu
Slide 8
Metals with More than One Common Oxidation Number Here are some
of the more commonly used transition metals and their oxidation
numbers. Notice that a Roman numeral is used to indicate the charge
on the ion when naming the ions formed. Back to main menu Fe 2+
Iron(II) ionFe 3+ Iron(III) ion Cu + Copper(I) ionCu 2+ Copper(II)
ion Hg 2 2+ Mercury(I) ionHg 2+ Mercury(II) ion Pb 2+ Lead(II)
ionPb 4+ Lead(IV) ion Sn 2+ Tin(II) ionSn 4+ Tin(IV) ion Cr 2+
Chromium(II) ionCr 3+ Chromium(III) ion Cr 6+ Chromium(VI) ion Mn
2+ Manganese(II) ionMn 3+ Manganese(III) ion Co 2+ Cobalt(II) ionCo
3+ Cobalt(III) ion Ni 2+ Nickel(II) ionNi 3+ Nickel(III) ion Ag +
Silver ion Zn 2+ Zinc ion Cd 2+ Cadmium ion
Slide 9
Negative Ions An anion is an atom or group of atoms with a
negative charge. An anion has more electrons than a neutral atom of
the element. Group 17 forms -1 ions. Group 16 forms -2 ions. Group
15 forms -3 ions. The names of monatomic anions end in ide. Back to
main menu
Slide 10
Naming and Writing Formulas for Anions Back to main menu
ElementSymbol of IonName of Ion Chlorine Nitrogen Oxygen Cl -
Chloride ion N 3- Nitride ion O 2- Oxide ion
Slide 11
You Try It Complete the following table. S 2- Back to main menu
Symbol of Ion Name of IonNumber of Electrons Lost or Gained Sulfide
ion Cu + Barium ion Al 3+ Iron(III) ion Li + Phosphide ion 2 e -
gained Copper(I) ion 1 e - lost Ba 2+ 2 e - lost Aluminum ion 3 e -
lost Fe 3+ 3 e - lost Lithium ion 1 e - lost P 3- 3 e - gained
Slide 12
Predicting Formulas of Ionic Compounds Ionic compounds are
composed of charged particles called ions. They are electrically
neutral. This means that the total positive charge is equal to the
total negative charge. Binary ionic compounds usually consist of a
metal, such as an alkali metal, bonded to a nonmetal, such as a
halogen. Empirical formulas are used to represent ionic compounds.
An empirical formula is the simplest ratio in which the atoms
combine to form a compound. Back to main menu
Slide 13
Predicting Formulas of Ionic Compounds Examples: Write the
formulas for the compounds formed between the following pairs of
ions. Back to main menu a. K +, Cl - b.Mg 2+, S 2- c.Na +, S 2-
d.Al 3+, S 2- e.Sn 4+, O 2- KCl MgS Na 2 S Al 2 S 3 SnO 2
Slide 14
You Try It Write the formulas for the following binary ionic
compounds. Hint: First determine the symbols for the ions involved.
Always write the cation first. The first one has been done for you
as an example. Back to main menu a.Sodium bromide b.Magnesium
sulfide c.Copper(I) chloride d. Calcium bromide e.Strontium
fluoride Na +, Br - Mg 2+, S 2- Cu +, Cl - Ca 2+, Br - Sr 2+, F -
NaBr MgS CuCl CaBr 2 SrF 2
Slide 15
You Try It Write the formulas for the following binary ionic
compounds. Hint: First determine the symbols for the ions involved.
Always write the cation first. The first one has been done for you
as an example. Back to main menu f.Sodium oxide g.Lead(II) bromide
h.Zinc sulfide i.Aluminum oxide j.Chromium(VI) nitride Na +, O 2-
Pb 2+, Br - Zn 2+, S 2- Al 3+, O 2- Cr 6+, N 3- Na 2 O PbBr 2 ZnS
Al 2 O 3 CrN 2
Slide 16
Naming Binary Ionic Compounds Binary ionic compounds are named
by writing the name of the cation followed by the name of the anion
(-ide ending). Back to main menu a.Na 2 S b.LiF c.BaCl 2 Sodium
sulfide Lithium fluoride Barium chloride
Slide 17
Roman Numerals Sometimes it is necessary to use a Roman numeral
when naming an ionic compound. Back to main menu When do you use a
Roman numeral when naming an ionic compound? You use a Roman
numeral when the metallic element forms more than one common ion.
This is common of the transition metals. CuCl is CuCl 2 is
Copper(I) Chloride Copper(II) Chloride
Slide 18
Roman Numerals Never use a Roman numeral when the metallic
element is from Group 1, Group 2, or for aluminum, cadmium, zinc or
silver. Back to main menu Circle the compounds below that would
need a Roman numeral when naming them. SnCl 2 Fe 2 O 3 BaCl 2 LiF
MgS CaO SrF 2 CoI 3
Slide 19
Roman Numerals How do I determine the charge of the Roman
numeral? Back to main menu To determine the charge of the Roman
numeral you have to first identify the ions making up the
compound.
Slide 20
Roman Numerals Examples. Back to main menu Fe 2 O 3 Iron(III)
oxide Ions Chemical Formula Name of Compound Fe 3+, O 2- Cu +, S 2-
CoI 2 Tin(IV) oxide FeS Cu 3 N Cu 2 SCopper(I) sulfide Co 2+, I -
Cobalt(II) iodide Sn 4+, O 2- SnO 2 Fe 2+, S 2- Iron(II) sulfide Cu
+, N 3- Copper(I) nitride
Slide 21
You Try It Write formulas for the following compounds. Remember
to determine the ions involved first. Back to main menu Name of
CompoundIons Formula of Compound Lithium oxide Tin(IV) sulfide
Barium nitride Sodium fluoride Li 2 OLi +, O 2- Sn 4+, S 2- SnS 2
Na +, F - Ba 2+, N 3- Ba 3 N 2 NaF
Slide 22
You Try It Name the following compounds. Back to main menu
a.CaS b.FeN c.K 2 O d.PbO Calcium sulfide Iron(III) nitride
Potassium oxide Lead(II) oxide
Slide 23
Naming and Writing Formulas for Ternary Ionic Compounds Ternary
ionic compounds contain more than two elements. They usually
contain one or more polyatomic ions. Back to main menu Common
Polyatomic Ions 1 - Charge2 - Charge3 - Charge PerchlorateClO 4 -
CarbonateCO 3 2- PhosphatePO 4 3- ChlorateClO 3 - SulfateSO 4 2-
PhosphitePO 3 3- ChloriteClO 2 - SulfiteSO 3 2- HypochloriteClO -
ChromateCrO 4 2 1 + Charge NitrateNO 3 - DichromateCr 2 O 7 2-
AmmoniumNH 4 + NitriteNO 2 - OxalateC 2 O 4 2- IodateIO 3 -
SilicateSiO 3 2- BromateBrO 3 - Hydrogen PhosphateHPO 4 2-
PermanganateMnO 4 - HydroxideOH - CyanideCN - AcetateC2H3O2-C2H3O2-
Dihydrogen phosphateH 2 PO 4 - Hydrogen Sulfite (bisulfate) HSO 3 -
Hydrogen sulfate (bisulfate) HSO 4 - Hydrogen carbonate
(bicarbonate) HCO 3 -
Slide 24
Writing Formulas for Ternary Ionic Compounds Writing the
formulas for ternary ionic compounds is just like writing the
formula for binary ionic compounds. You write the symbol and charge
of the ions involved and then balance the charges. Back to main
menu
Slide 25
Writing Formulas for Ternary Ionic Compounds Examples: Back to
main menu a.K +, NO 3 - b.Ba 2+, PO 4 3- KNO 3 Ba 3 (PO 4 ) 2
Slide 26
You Try It 1.Write the formulas for the following ternary ionic
compounds, given the ions involved. Back to main menu a.Ca 2+, SO 4
2- b.K +, PO 4 3- c.NH 4 +, N 3- d.Al 3+, SO 4 2- CaSO 4 K 3 PO 4
(NH 4 ) 3 N Al 2 (SO 4 ) 3
Slide 27
You Try It 2.Write the formulas for the following ternary ionic
compounds given their names. Back to main menu Lithium hypochlorite
Sodium sulfite Calcium acetate Barium phosphate Copper(II) nitrite
LiClO Na 2 SO 3 Ca(C 2 H 3 O 2 ) 2 Ba 3 (PO 4 ) 2 Cu(NO 2 ) 2 Li +,
ClO - Na +, SO 3 2- Ca 2+, C 2 H 3 O 2 - Ba 2+, PO 4 3- Cu 2+, NO 2
-
Slide 28
You Try It 3.To name a compound, write the name of the cation
followed by the name of the anion. Back to main menu a. Ca(NO 3 ) 2
b. K 2 SO 4 c. PbSO 3 d. NaC 2 H 3 O 2 e. (NH 4 ) 2 S Calcium
nitrate Potassium sulfate Lead(II) sulfite Sodium Acetate Ammonium
sulfide