Unit 3: Bonding
Chemicals are…Everywhere!
Everything!
 A _______________ that has a __________ composition.
 Matter – anything that has _____ and ______
 Volume – the amount of ________ an object occupies
 Mass – the ________ of ________ in an object
 Weight – the amount of ________ force acting on an object
Classification of Matter
Pure Substances
 Element – a ________ type of ________
o atom – the ________ single unit that ________ all of the
________ of the element
 Compound – made up of ________ than one ________
o simplest unit is the ________ (must retain all ________
with a consistent ratio of atoms)
Molecule
 Any unit containing ________ than one ________
o E.g. oxygen molecule (O2) is an ________
o carbon dioxide molecule (CO2) is a ________
Mixtures
 Contains ________ or more ________ substances
o ________ geneous – has ________ distribution of
substances
o ________ geneous – ________ distribution (can often
see layers or regions)
Physical States of Matter





Bose-Einstein Condensate
________________
________________
________________
plasma
Bose-Einstein Condensate
 Fixed volume and shape
 Molecules move in ________
Solid
 fixed volume and shape
 Molecules/atoms ________ in their position
Liquid
 Fixed volume, variable shape (shape of container)
 Molecules/atoms can move around each other, but
________ in ________
Gas
 Volume & shape of container
 Molecules/atoms move in ________ lines until they run
into something that changes their course
 Only weakly ________ to each other
Plasma
 Gas particles that have gained enough energy to become
electrically charged
 E.g. Lightning, fire
Ionic vs. Covalent Compounds
 Ionic compounds – contain a ________
 Covalent compounds – ________ non-metals
Covalent or Ionic?
H2O
NaCl
HgSO4
PF4
Valence Electrons
 ________ shell electrons involved in ________
 Remember ________ group numbers
Ionic Bonds – ________ electrons
 one or more electrons leave on atom and join another
 a cation (________ ) and an anion (________ ) form
 cation sticks to anion like a magnet
Covalent Bonds – ________ electrons
 ________ atom loses or gains electrons
Electronegativity
 the ability of an atom to ________ electrons involved in
________ with another atom
 values ________ the type of bonding that will occur
EN Difference
< 0. 5
0.5 – 2.1
2.1
Type of Bond
________________ (even sharing)
________________ (uneven sharing)
________________ (electrons transfer)
What type of bond is formed?
KCl
NH
PS
Diatomic Elements
 elements not found ________ in nature
 memorize these! (think 7)
Covalent Nomenclature
MEMORIZE THIS!
1 - _______________
2 - _______________
3 - _______________
4 - _______________
5 - _______________
6 - _______________
7 - _______________
8 - _______________
9 - _______________
10 - _______________
First element:
prefix (except mono) + name of element
Second element:
prefix + root of element name + ide ending
Name the following
SeI4
CSe2
N2O3
P2Cl5
Write formulas for the following
phophorus pentabromide
disulfur trioxide
aresenic trifluoride
dichlorine monoxide
Lewis Dot Structures
 ________ that show how electrons are ________ between
atoms in ________ bonds
 Use only ________ electrons
Lewis Structures for Atoms
Na
C
Special
S
H
I
Ne
He
Octet Rule
 All atoms want ________ valence electrons
 Atoms will ________ to satisfy this rule
Exceptions!
 ________ and ________ only want ________ electrons!
Covalent Bonds
 Single bond =
 Double bond =
 Triple bond =
________ pair of ________ electrons
________ pair of ________ electrons
________ pair of ________ electrons
Drawing Lewis Structure for Molecules
 Find the total number of ________ electrons
 Determine the ________ atom
- usually first
S
in SO4
- or only one
O in H2O
- or in the middle
O in HOCl2
 Place ________ bonds between atoms
 Place ________ ________
 Check ________ rule & total number of electrons
 If needed add ________ or ________ bonds ________ at a
time
Practice Drawing Lewis Structures
CH4
NH3
CSe2
CO
H 2O
HCN
Polyatomic Ions
 Add or subtract the appropriate number of ________
NH4+
SO4-2
Resonance
 When ________ than ________ Lewis Structure is possible
O3
NO3-
CO3-2
Molecular Geometries
 describe the ________ shape of a molecule
 VSEPR – ________ ________ ________ ________ ________
 ________ Lewis Structure
 ________ bonds (doesn’t matter what type)
 ________ lone pairs (unshared pairs of electrons)
Drawing 3-D Lewis Structures
_______
-----------
(solid line)
(dotted line)
(wedge)
CO2
in the plane of the page
away from the reader
toward reader
SO2
CH2O
NH3
CH4
H 2O
Polar or Non-Polar?
 Polar molecules are ________
 When cut in half (any direction) the two sides will be
________
 Look for
o ________ ________ on the central atom
o ________ atoms bonded to the central atom
Polar or Non-Polar?
CO2
SO2
CH2O
CH4
NH3
H 2O
Ionic Compounds
 EN difference is ________ (> 2.1)
 electrons are ________ – NOT ________
 ________ – atom (or group of atoms) that ________
electrons
 ________ – atom (or group of atoms) that ________
electrons
 #electrons lost ________ # electrons gained
 charges for entire compound must add up to ________
Ionic Nomenclature
 monoatomic ________ = name of element
o Na+
sodium ion
 monoatomic ________ = root of element name + ________
ending
o Clchloride ion
 polyatomic ions – see chart
 check memory work!
 compound name = cation name + anion name
 ________ PREFIXES