Ionic and Covalent Bonding
Including Naming
Note: We likely won’t make it to covalent nomenclature, this is the one students find
FAR easier than ionic. Please refer to the videos and naming hand out for help with
this, and as always office hours, discussions, and facebook for extra help. If you
don’t remember it from high school/1P.
TYPES OF BONDS
Ionic:
Covalent:
Metallic:
•“trades” electrons
• Metal and a non-metal
(oversimplified definition)
•“shares” electrons
•non-metals
(oversimplified definition)
•delocalized electrons
•metals
•electrically conductive
•collective description of many bonds
NaCl
CO
Ag
For the Following Choose the Ionic Compounds
(based on previous definition)
• NaCl
• CH3Cl
• MgCl2
• SO2
• Na2SO3
For the binary ionic compounds in the last slide, decide
which has more covalent character.
Reminder note from videos (see slides
included FYI):
NaCl
MgCl2
Summary of slides:
The more polarizing power and
polarizability lead to a bond with
more covalent character.
Small highly charged cations have more
polarizing power.
Large highly negatively charged cations have
more polarizability.
For cations which have more polarizability?
POLARIZING POWER POLARIZABILITY AND COVALENT
CHARACTER
• Polarizability: Anion
NaC l
MgI2
• More electrons that are further from the nucleus
• Nucleus has less pull on far off electrons. The more energy
shells the more polarizability
• A more negative charge, higher electron:proton ratio, more
polarizability
• Polarizing power: Cation
• Less electrons closer to the nucleus
• Nucleus has larger effect on electrons if they are closer to the
nucleus. Less electron shells equal more polarizing power
• A more positive charge, higher proton:electron ratio, higher
polarizing power
POLARIZING POWER POLARIZABILITY AND COVALENT
CHARACTER
NaCl
MgI2
• More polarizability/polarizing power of the
anion/cation leads to a bond with more covalent
character
Note: This isn’t and won’t be covered in
the videos.
You won’t need to do lattice energy
problems any more complex than
shown in the next couple of slides.
LATTICE ENERGIES
We will not be calculating the numbers,
this equation will be for illustration
purposes only.
Charge
Ion 1
Charge
Ion 2
If charge increases what happens to energy?
If internuclear distance increases what happens to energy?
Internuclear
radius
Ionic Bond Formation
• A) Explain why the lattice energy of silver bromide (903 kJ/mol) is greater than
that of silver iodide (887 kJ/mol), given that they have a similar arrangement of
ions .
• Hint: How does the charge of Br- and I- compare?
• Hint: How does the size of Br- and I- compare?
• Hint: If two charges are closer together, how is the force required to hold them
together affected?
NAMING: IONIC
• Name the Compounds we identified as ionic on the first
problem.
• NaCl
• MgCl2
• Na2SO3
NAMING: COVALENT
• Name the Compounds below.
• SO2
• NO
• PCl5