Ionic Ionic Compounds:Compounds:Names and Names and FormulasFormulasSNC2DSNC2D
Counting IonsCounting IonsSodium chloride or NaCl Sodium chloride or NaCl
contains 1 sodium ion and 1 chloride contains 1 sodium ion and 1 chloride ion.ion.
(Lewis dot diagrams)(Lewis dot diagrams)
Counting IonsCounting IonsHowever, different ions may form However, different ions may form
compounds in different ratios. compounds in different ratios.
For example, calcium chloride or CaClFor example, calcium chloride or CaCl22 contains 1 calcium ion and 2 chloride ions.contains 1 calcium ion and 2 chloride ions.
(Subscripts are added to the symbols in a (Subscripts are added to the symbols in a formula if there is more than one of that formula if there is more than one of that type of atom.)type of atom.)
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33
NaNa22O O
CaOCaO
FeFe22OO33
NaClONaClO33
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O O
CaOCaO
FeFe22OO33
NaClONaClO33
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO
FeFe22OO33
NaClONaClO33
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO containscontains 1 calcium ion and 1 oxide ion1 calcium ion and 1 oxide ion
FeFe22OO33
NaClONaClO33
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO containscontains 1 calcium ion and 1 oxide ion1 calcium ion and 1 oxide ion
FeFe22OO33 contains contains 2 iron ions and 3 oxide ions2 iron ions and 3 oxide ions
NaClONaClO33
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO containscontains 1 calcium ion and 1 oxide ion1 calcium ion and 1 oxide ion
FeFe22OO33 contains contains 2 iron ions and 3 oxide ions2 iron ions and 3 oxide ions
NaClONaClO33 contains contains 1 sodium ion and 1 chlorate ion1 sodium ion and 1 chlorate ion
NaNa22COCO33
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO containscontains 1 calcium ion and 1 oxide ion1 calcium ion and 1 oxide ion
FeFe22OO33 contains contains 2 iron ions and 3 oxide ions2 iron ions and 3 oxide ions
NaClONaClO33 contains contains 1 sodium ion and 1 chlorate ion1 sodium ion and 1 chlorate ion
NaNa22COCO33 contains contains 2 sodium ions and 1 carbonate ion2 sodium ions and 1 carbonate ion
Ca(ClOCa(ClO33))22
Counting Ions: PracticeCounting Ions: PracticeFeClFeCl33 containscontains 1 iron ion and 3 chloride ions1 iron ion and 3 chloride ions
NaNa22O containsO contains 2 sodium ions and 1 oxide ion2 sodium ions and 1 oxide ion
CaOCaO containscontains 1 calcium ion and 1 oxide ion1 calcium ion and 1 oxide ion
FeFe22OO33 contains contains 2 iron ions and 3 oxide ions2 iron ions and 3 oxide ions
NaClONaClO33 contains contains 1 sodium ion and 1 chlorate ion1 sodium ion and 1 chlorate ion
NaNa22COCO33 contains contains 2 sodium ions and 1 carbonate ion2 sodium ions and 1 carbonate ion
Ca(ClOCa(ClO33))22 contains contains 1 calcium ion and 2 chlorate 1 calcium ion and 2 chlorate ionsions
Why These Ratios?Why These Ratios?It is the valence electrons that It is the valence electrons that
determine how these ions combine.determine how these ions combine.For example, calcium had 2 valence For example, calcium had 2 valence
electrons to lose and each chlorine electrons to lose and each chlorine only wants 1. So calcium has to find only wants 1. So calcium has to find 2 chlorines.2 chlorines.
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form following combine to form compounds:compounds:MgMg2+2+ and Br and Br1-1-
LiLi1+1+ and P and P3-3-
CaCa2+2+ and O and O2-2-
AlAl3+3+ and OH and OH1-1-
KK1+1+ and SO and SO442-2-
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form following combine to form compounds:compounds:MgMg2+2+ and Br and Br1-1- MgBrMgBr22
LiLi1+1+ and P and P3-3-
CaCa2+2+ and O and O2-2-
AlAl3+3+ and OH and OH1-1-
KK1+1+ and SO and SO442-2-
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form compounds:following combine to form compounds:MgMg2+2+ and Br and Br1-1- MgBrMgBr22
LiLi1+1+ and P and P3-3- LiLi33PPCaCa2+2+ and O and O2-2-
AlAl3+3+ and OH and OH1-1-
KK1+1+ and SO and SO442-2-
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form compounds:following combine to form compounds:MgMg2+2+ and Br and Br1-1- MgBrMgBr22
LiLi1+1+ and P and P3-3- LiLi33PPCaCa2+2+ and O and O2-2- CaOCaOAlAl3+3+ and OH and OH1-1-
KK1+1+ and SO and SO442-2-
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form compounds:following combine to form compounds:MgMg2+2+ and Br and Br1-1- MgBrMgBr22
LiLi1+1+ and P and P3-3- LiLi33PPCaCa2+2+ and O and O2-2- CaOCaOAlAl3+3+ and OH and OH1-1- Al(OH)Al(OH)33
KK1+1+ and SO and SO442-2-
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form compounds:following combine to form compounds:MgMg2+2+ and Br and Br1-1- MgBrMgBr22
LiLi1+1+ and P and P3-3- LiLi33PPCaCa2+2+ and O and O2-2- CaOCaOAlAl3+3+ and OH and OH1-1- Al(OH)Al(OH)33
KK1+1+ and SO and SO442-2- KK22SOSO44
Ratio PracticeRatio PracticeUse diagrams to determine how the Use diagrams to determine how the
following combine to form following combine to form compounds:compounds:
AlAl3+3+ and O and O2-2- AlAl22OO33
Notice that the quick method of Notice that the quick method of determining the formula is to criss-determining the formula is to criss-cross the valences:cross the valences:
Criss-crossCriss-crossBut the ratio between the ions must But the ratio between the ions must
be reduced to lowest terms (and 1s be reduced to lowest terms (and 1s are not written).are not written).
E.g. PbE.g. Pb4+4+ and O and O2-2- becomes becomes
?? notnot Pb Pb22OO44
Criss-crossCriss-crossBut the ratio between the ions must be But the ratio between the ions must be
reduced to lowest terms (and 1s are not reduced to lowest terms (and 1s are not written).written).
E.g. PbE.g. Pb4+4+ and O and O2-2- becomes becomes
PbOPbO22 notnot Pb Pb22OO44
Please complete “More Formula Practice.”Please complete “More Formula Practice.”
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is The name of an ionic compound is
simply the name of the positive ion simply the name of the positive ion followed by the name of the negative followed by the name of the negative ion, e.g.:ion, e.g.:
NaClNaClCaClCaCl22 LiLi22O O
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is The name of an ionic compound is
simply the name of the positive ion simply the name of the positive ion followed by the name of the negative followed by the name of the negative ion, e.g.:ion, e.g.:
NaClNaCl is is sodium chloridesodium chlorideCaClCaCl22 LiLi22O O
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is The name of an ionic compound is
simply the name of the positive ion simply the name of the positive ion followed by the name of the negative followed by the name of the negative ion, e.g.:ion, e.g.:
NaClNaCl is is sodium chloridesodium chlorideCaClCaCl22 is is calcium chloridecalcium chlorideLiLi22OO
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is The name of an ionic compound is
simply the name of the positive ion simply the name of the positive ion followed by the name of the negative followed by the name of the negative ion, e.g.:ion, e.g.:
NaClNaCl is is sodium chloridesodium chlorideCaClCaCl22 is is calcium chloridecalcium chlorideLiLi22O O is is lithium oxidelithium oxide
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is The name of an ionic compound is
simply the name of the positive ion simply the name of the positive ion followed by the name of the negative followed by the name of the negative ion, e.g.:ion, e.g.:
KOHKOHMg(ClOMg(ClO33))22 NHNH44F F
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is simply The name of an ionic compound is simply
the name of the positive ion followed the name of the positive ion followed by the name of the negative ion, e.g.:by the name of the negative ion, e.g.:
KOHKOH is is potassium hydroxidepotassium hydroxideMg(ClOMg(ClO33))22 NHNH44F F
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is simply The name of an ionic compound is simply
the name of the positive ion followed by the name of the positive ion followed by the name of the negative ion, e.g.:the name of the negative ion, e.g.:
KOHKOH is is potassium hydroxidepotassium hydroxideMg(ClOMg(ClO33))22 is is magnesium chloratemagnesium chlorateNHNH44F F
Ionic Compounds: NamesIonic Compounds: NamesThe name of an ionic compound is simply The name of an ionic compound is simply
the name of the positive ion followed by the name of the positive ion followed by the name of the negative ion, e.g.:the name of the negative ion, e.g.:
KOHKOH is is potassium hydroxidepotassium hydroxideMg(ClOMg(ClO33))22 is is magnesium chloratemagnesium chlorateNHNH44F F is is ammonium fluorideammonium fluoride
Names with Multivalent Names with Multivalent IonsIons
The only tricky ones to name are those that The only tricky ones to name are those that contain multivalent ions. It is necessary contain multivalent ions. It is necessary to look at how the ions have combined to to look at how the ions have combined to figure out the valence of the multivalent figure out the valence of the multivalent ion.ion.
FeOFeO must bemust be
FeFe22OO33 must bemust be
Names with Multivalent Names with Multivalent IonsIons
The only tricky ones to name are those that The only tricky ones to name are those that contain multivalent ions. It is necessary contain multivalent ions. It is necessary to look at how the ions have combined to to look at how the ions have combined to figure out the valence of the multivalent figure out the valence of the multivalent ion.ion.
FeOFeO must bemust be iron (II) oxideiron (II) oxide(because oxide is O(because oxide is O2-2-))FeFe22OO33 must bemust be
Names with Multivalent Names with Multivalent IonsIons
The only tricky ones to name are those that The only tricky ones to name are those that contain multivalent ions. It is necessary contain multivalent ions. It is necessary to look at how the ions have combined to to look at how the ions have combined to figure out the valence of the multivalent figure out the valence of the multivalent ion.ion.
FeOFeO must bemust be iron (II) oxideiron (II) oxide(because oxide is O(because oxide is O2- 2- and the ratio is 1:1)and the ratio is 1:1)FeFe22OO33 must bemust be iron (III) oxideiron (III) oxide
Names with Multivalent Names with Multivalent IonsIons
Try it with copper:Try it with copper:
CuClCuCl22
CuSOCuSO44
CuCu22OO
Names with Multivalent Names with Multivalent IonsIons
Try it with copper:Try it with copper:
CuClCuCl22 copper (II) chloridecopper (II) chloride
CuSOCuSO44
CuCu22OO
Names with Multivalent Names with Multivalent IonsIons
Try it with copper:Try it with copper:
CuClCuCl22 copper (II) chloridecopper (II) chloride
CuSOCuSO44 copper (II) sulphatecopper (II) sulphate
CuCu22OO
Names with Multivalent Names with Multivalent IonsIons
Try it with copper:Try it with copper:
CuClCuCl22 copper (II) chloridecopper (II) chloride
CuSOCuSO44 copper (II) sulphatecopper (II) sulphate
CuCu22OO copper (I) oxidecopper (I) oxide