Notes

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Ionic Compounds
Ionic Bonding
Electrons are transferred from one atom to
another so that each has 8 valence electrons
- called the octet rule
+
Cation
Anion
Ionic Compound
Ionic bond: bond formed by attraction
between + and - ions
Ionic Bonding
Ionic bonds occur between metals and non-metals
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
Cs
Ba
Lu
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
Fr
Ra
Lr
Rf
Db
Sg
Bh
Hs
Mt
Uun
Uuu
Uub
Uut
Metals
Metalloids
Non-metals
The “magic number” is 8!
Binary Ionic Compounds
Formula to Name
The Language of Chemistry
Chemistry has a language all of its own
Chemistry
English
Element Symbols
Letters
Chemical Formulas
Words
Chemical Equations
Sentences
Each element symbol starts with a capital letter
Binary Ionic:
Formula to Name
• These compounds have:
– 2 elements (“binary”)
– A metal & a non-metal (“ionic”)
• To name:
1. Name of the metal (the cation)
2. Name of the non-metal (the anion) with the suffix
“-ide”
The subscripts in the formula do not matter when
naming this type
Example
CaBr2
Example
K2O
Let’s Practice
Example:
Write the name
for the following
compounds
CaF2
Na3P
NaI
SrBr2
Let’s Practice
Example:
Write the name
for the following
compounds
CaF2
Calcium fluoride
Na3P
Sodium phosphide
NaCl
Sodium chloride
SrBr2
Strontium bromide
Binary Ionic Compounds
Name to Formula
Binary Ionic:
Name to Formula
• These compounds:
– End in “-ide” (except “hydroxide and cyanide”)
– Do NOT contain covalent prefixes
• To write:
1. Draw Lewis dot diagrams of each element and transfer
electrons.
2. Use subscripts to show how many of each type of ion you
have.
Example
Sodium fluoride
Let’s Practice
Example:
Write the
following
chemical
formulas
Cesium chloride
Potassium oxide
Calcium sulfide
Lithium nitride
Let’s Practice
Example:
Write the
following
chemical
formulas
Cesium chloride
CsCl
Potassium oxide
K2O
Calcium sulfide
CaS
Lithium nitride
Li3N
Multivalent Ionic Compounds
Formula to Name
Multivalent (Transition) Metals
Multivalent Metal: a metal that has more
than one possibility for cationic (positive)
charge
The Appendix of your book (Page A-2) has the following chart
Common multivalent metals and their charges
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Tin
Co+2
Cu+1
Fe+2
Pb+2
Mn+2
Hg2+2
Sn+2
Co+3
Cu+2
Fe+3
Pb+4
Mn+3
Hg+2
Sn+4
Multivalent Metals:
Formula to Name
• To identify:
– Have a transition metal
• To name:
1.
2.
3.
4.
5.
6.
Name of the metal cation
Name of the anion
Determine total negative charge in the compound
Total negative charge must = total positive charge
Determine the charge on each metal atom
Write the charge in roman numerals in parenthesis after the
metal’s name
Example
Anion
CuCl2
Total
Total
negative
positive
charge in
charge in
compound compound
Cation
Name
Example
Anion
Fe2O3
Total
Total
negative
positive
charge in
charge in
compound compound
Cation
Name
Let’s Practice
PbCl2
Example:
Write the name
for the following
compounds
PbCl4
MnO
Mn2O7
Let’s Practice
Example:
Write the name
for the following
compounds
PbCl2
Lead (II) chloride
PbCl4
Lead (IV) chloride
MnO
Manganese (II) oxide
Mn2O3
Manganese (VII) oxide
Multivalent Ionic Compounds
Name to Formula
Multivalent Metals:
Name to Formula
• To identify:
– Will have roman numerals
• To write:
– Same as binary!
• Roman numerals tell the charge of the metal
cation
Example
Iron (III) oxide
Example
Copper (I) nitride
Let’s Practice
Example:
Write the
following
chemical
formulas
Iron (II) nitride
Copper (I) chloride
Lead (IV) sulfide
Tin (II) oxide
Let’s Practice
Example:
Write the
following
chemical
formulas
Iron (II) nitride
Fe3N2
Copper (I) chloride
CuCl
Lead (IV) sulfide
PbS2
Tin (II) oxide
SnO
Polyatomic Ionic Compounds
Polyatomic Ions
Polyatomic Ion: a group of atoms that has
lost or gained electrons. Therefore, it has a
charge!
Polyatomic Ionic Compound: compound
containing at least one polyatomic ion
+
Cation
Polyatomic
Anion
Polyatomic Ionic
Compound
Identifying Polyatomic Ions
• Only one cation: NH4+
• All others are anions (second part of formula)
• Subscripts must match exactly as it appears on
your list
• If there are parenthesis, the polyatomic ion is
inside
Practice Identifying Polyatomic
Ions
Example:
Identify and
name the
polyatomic ion in
each compound
NaNO3
NH4Cl
Ca(OH)2
(NH4)3PO4
K2CO3
Practice Identifying Polyatomic
Ions
Example:
Identify and
name the
polyatomic ion in
each compound
NaNO3
Nitrate
NH4Cl
Ammonium
Ca(OH)2
Hydroxide
(NH4)3PO4
Ammonium &
phosphate
K2CO3
Carbonate
Polyatomic Ionic Compounds
Name to Formula
Polyatomic Ionic:
Name to Formula
•
•
To identify:
– Do not end with “-ide” (except hydroxide & cyanide)
– Do not use covalent prefixes
To write these formulas:
1. Write the symbol & charge of the cation & anion
2. Add additional cations or anions to have a neutral
compound
3. Use subscripts to show the number of ions
- When using subscripts with a polyatomic ion, you must
put the polyatomic ion in parenthesis.
Example
Sodium carbonate
Example
Magnesium nitrate
Let’s Practice
Example:
Write the
following
chemical
formulas
Sodium nitrate
Calcium chlorate
Potassium sulfite
Calcium hydroxide
Let’s Practice
Example:
Write the
following
chemical
formulas
Sodium nitrate
NaNO3
Calcium chlorate
Ca(ClO3)2
Potassium sulfite
K2SO3
Calcium hydroxide
Ca(OH)2
Polyatomic Ionic Compounds
Formula to Name
Polyatomic Ionic:
Formula to Name
• To identify:
– More than 2 capital letters (not starting with H)
– at least 1 metal & 1 non-metal
• To name:
1. Name of the cation
2. If the anion is a polyatomic ion, write the
polyatomic ion’s name just as it is
3. If the anion is a single non-metal element, use
“-ide”
Example
NaNO3
Example
Fe(OH)
2
Let’s Practice
Ca(NO3)2
Example:
Write the name
for the following
compounds
Na3PO4
NH4ClO
K2CO3
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