Reminder…
From chapter 2 – The arrangement of “ground state”
electrons in atoms
▪ Know the components of an electron configuration
o Principal energy level (“shell”)
o Orbital - Orbital shapes and orientations
o Number of electrons
▪ Know how to write an electron configurations
▪ Relate electron configurations to the Periodic Table
▪ Know how to write orbital “box” diagrams and how they
relate to orientations of orbitals
Main group elemen ts;
s block (2 elemen ts )
1A
Main group elemen ts;
p block (6 elemen ts )
8A
3A 4A 5A 6A 7A 1s 1
Tran sition elemen ts;
d block (10 elemen ts )
1 1s 2A
Heliu m is
als o an s block
element
2p
2
3
3d
3p
5p
4p
5s
4d
4p
5p
5
6
6s
5d
6p
6
7
7s
6d
7p
7
2
2s
3
3s
4
4s
5
3B 4B 5B 6B 7B 8B 8B 8B 1B 2B
Inn er transition
elements; f block
(14 elemen ts)
6
4f
7
5f
4
▪ Be
aware that atoms will either lose, gain or share
electrons to form a chemical bond
 Losing electrons results in a positive charge on an
atom or group of atoms
cation
 Gaining electrons results in a negative charge on
an atom or group of atoms
anion
 Sharing electrons results in no charge on the
atom
▪
Know there are two main types of chemical bonds
1. Ionic: electrostatic bond between charged entities
called ions
 Positive ions: cation (single or multiple atoms)
 Negative ions: anion (single or multiple atoms)
2. Covalent: bond formed between two atoms by the
sharing of their electrons
 Know the general approach to identify
between formulas of covalent and ionic
compounds
o Covalent: All nonmetals
o Ionic: Metal followed by nonmetals
Chapter 3 – Ionic & Covalent (molecular) Compounds
Learn how to identify and write the names of…
Ionic
a. Made of charged species - Cation (+) & Anion (-)
i. Cation
1. Positively charged
2. Most are monatomic metals - one
exception is NH4+, a polyatomic
nonmetal ion
ii. Anions
1. Negatively charged
2. Some are monatomic nonmetals and
some are polyatomic nonmetals
b. Consist of one type of cation and one type of
anion
c. Cations & Anions are bonded by an IONIC
BOND – electrostatic attraction
d. Identified by - METALNONMETAL
Covalent (molecular)
a. Made of neutral atoms
b. Atoms are bonded by a COVALENT BOND – outer “shell”
electrons are shared between atoms
c. Identified by all NONMETALS
i. Binary (two different types of atoms)
Monatomic Ions
A single atom with a charge
▪ Monatomic cations are positively charged metal ions
 Main group cations retain the name of the metal  Transition group cations retain the name of the
metal but may have a roman numeral following
the name if multiple charge states exist
▪ Monatomic anions are negatively charged nonmetals
the suffix “ide” is added to the name of the nonmetal
 Know how to determine the charge of monatomic
ions
o Use the Periodic Table
o Use basic math
Memorize these Charges on Ions in Groups 1A, 2A, 5A-7A
The charge varies for particular transition metal atoms, so roman
numerals must be used. The charge can be determined by simple
math.
Memorize common exceptions: Ag+, Zn2+, Cd2+, Ni2+, Al3+
The total number of positive charges must equal
the total number of negative charges.
– AlCl3 is aluminum chloride
– LiBr is lithium bromide
– Ag2S is silver sulfide
– MgO is magnesium oxide
– KCl is potassium chloride
Ion
+
Cu
Cu2+
Systematic
name
Copp er(I) ion
Copp er(II) ion
Common
name
Cup rous ion
Cup ric ion
Origin of the sym
element or th e co
name of th e ion
Cupr- from cupr
name for copper
Fe 2 +
Fe 3 +
Iron(II) ion
Iron(III) ion
Ferrous ion
Ferric ion
Ferr- from ferrum
name for iron
Hg + Mercury(I) ion Mercu rous ion Hg from hy drarg
Latin name for m
Hg 2+ Mercury(II) ion Mercu ric ion
2+
Sn
Sn 4+
Tin(II) ion
Tin(IV) ion
Stannous ion
Stannic ion
Sn from s tannum
Latin name for ti
For systematic names, use Roman numerals to
show charge on the metal ion
– CuO is copper(II) oxide
– Cu2O is copper(I) oxide
– FeO is iron(II) oxide
– Fe2O3 is iron(III) oxide
Polyatomic ions
Know that a polyatomic ion is two or more nonmetal atoms
(a few exceptions) with a collective charge that is usually
negative
▪ Know that each polyatomic ion has a distinct name –
Memorize, ammonium, acetate, hydroxide, nitrate,
carbonate, bicarbonate, sulfate, phosphate
EOC
– NaNO3 is sodium nitrate.
– CaCO3 is calcium carbonate.
– NaH2PO4 is sodium dihydrogen phosphate.
– NH4OH is ammonium hydroxide.
– FeCO3 is iron(II) carbonate.
– Fe2(CO3)3 is iron(III) carbonate.
– CuSO4 is copper(II) sulfate.
– lithium ion and bromide ion form LiBr
– barium ion and iodide ion form BaI2
– aluminum ion and sulfide ion form Al2S3
– sodium ion and bicarbonate ion form NaHCO3
– potassium ion and phosphate ion form K3PO4
Naming one class of covalent compounds –
Binary Covalent
Know the rules for using prefixes
• Molecular compound: a compound in which all bonds are
covalent.
• Naming binary molecular compounds:
– prefixes “di-”, tri-”, etc. are used to show the number of
atoms of each element; the prefix “mono-” is not used for
the first atom, i.e. carbon monoxide
– NO is nitrogen monoxide (nitric oxide)
– SF2 is sulfur difluoride
– N2O is dinitrogen monoxide (laughing gas)
Naming one class of covalent compounds – Binary
Covalent
Know the rules for using prefixes
Prefixes for first atom
Prefix
Amount
Di
2
Tri
3
Tetra
4
Penta
5
Hexa
6
Hepta
7
Octa
8
Nona
9
Deca
10
Prefixes for second atom
Prefix
Mono
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Nona
Deca
Amount
1
2
3
4
5
6
7
8
9
10
Know how to draw Lewis structures for covalent
compound
▪ Know how to use the guidelines below OR Gino’s pieces
of common bonding approach
1. Determine the number of valence electrons in the molecule.
2. Determine the arrangement of atoms in the molecule.
3. Connect the atoms by single bonds.
4. Show bonding electrons as a single line; show nonbonding
electrons as a pair of Lewis dots.
5. In a single bond, atoms share one pair of electrons; in a
double bond, they share two pairs, and in a triple bond they
share three pairs.
H
O
H
H
H 2O (8)
Water
H
H N H
H C H
H
N H 3 (8)
Ammon ia
H
H
C C
CH 4 (8)
Meth ane
H Cl
HCl (8)
Hyd rogen ch loride
O
H
H C C H
C
O
H
H
C2 H 4 (12)
C2 H 2 (10)
H
CH 2O (12)
Eth ylene
Acetylene
Formald ehyde
H
O
C
O
H
H 2CO 3 (24)
Carbonic acid
8 electron s in
th e valence
sh ell of sulfur
10 electron s in
the valence
shell of sulfur
: :
:
: :
12 electrons in
the valen ce
s hell of su lfu r
O
O S O
H-O-S-O-H
H-S-H
O
Hydrogen su lfid e S ulfu r d ioxid e
S ulfuric acid
• Examples
– draw a Lewis structure for hydrogen peroxide,
H2O2.
– draw a Lewis structure for methanol, CH3OH.
– draw a Lewis structure for acetic acid, CH3COOH.
Bond Angle & Molecular Geometry
Use Lewis Structures and the “green sheets” to:
▪ Predict the bond angle between the central and terminal
atoms
▪ Predict the electron pair and molecular geometries of a
molecule
Links &
Lone Pairs
The “green sheets”
Links &
Lone Pairs
Know how to predict individual bond polarity
A covalent bond is polar if there’s an unequal sharing of
electron “fuzz”. Use an electronegativity table…
Polar if there is more than 0.4 difference between their
electronegativity values.
Know how to predict overall molecular polarity
▪ Predict if a molecule is polar – an unequal sharing of
electron “fuzz”. Molecule is polar if…
There are lone pair electrons around the central atom
OR
The terminal atoms are different than each other
Draw Lewis Structure & Predict Polarity
:
8 electrons in
the valence
sh ell of P
H-P-H
H
Phosph in e
8 electron s in
th e valence
sh ell of sulfur
10 electrons in
the valence
shell of P
Cl
Cl
10 electrons in
th e valen ce
sh ell of P
Cl
Cl
P
Cl
Phosph orus pentachloride
10 electron s in
the valence
shell of sulfur
O
H-O-P-O-H
O-H
Phosph oric acid
: :
:
: :
12 electrons in
the valen ce
s hell of su lfu r
O
O S O
H-O-S-O-H
H-S-H
O
Hydrogen su lfid e S ulfu r d ioxid e
S ulfuric acid
Draw Lewis Structure & Predict Polarity
H
O
H
H
H 2O (8)
Water
H
H N H
H C H
H
N H 3 (8)
Ammon ia
H
H
C C
CH 4 (8)
Meth ane
H Cl
HCl (8)
Hyd rogen ch loride
O
H
H C C H
C
O
H
H
C2 H 4 (12)
C2 H 2 (10)
H
CH 2O (12)
Eth ylene
Acetylene
Formald ehyde
H
O
C
O
H
H 2CO 3 (24)
Carbonic acid