11/11/2016
Chemical Bonding
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Unit 5 Notes
By the end of this lesson
you will be able to:
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Name and describe the 3 types of
bonds and how they are different
List possible compounds in each and
how elements are affected by the
bonds they share
Describe how we know these bonds
exist. What are properties of the
bonds?
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Ionic Bonds
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Bond most often between a metal and a
nonmetal
Transfer of electrons from the metal to
the nonmetal
Electrical attraction between large
numbers of cations and anions called
clusters
Ion = a charged particle
Ionic Bonds
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Cation = + charged particle
– Loves to give electrons away
– Low Ionization Energy, Electron Affinity &
Electronegativity
– Typically are metals
– Most metallic element = Fr
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Ionic Bonds (cont.)
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Anion = - charged particle
– Loves to accept electrons
– High Ionization Energy, Electron Affinity
& Electronegativity
– Typically are nonmetals
– Most nonmetallic element = F
Ionic Bonds (cont.)
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If a bond is ionic:
– The compound is solid
– The compound will fall apart (dissociate)
into its original ions when dissolved in
water
-If a conductivity test is performed, the
light bulb will…
light!
-EN values 1.8 up to 4
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In General
Ionic Bonds are the
strongest bonds there are
Covalent Bonds
Formed when 2 nonmetal atoms share
electrons
Can be liquid, solid or gas
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Polar Covalent Bonds
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Unequal sharing of electrons
Electrons attracted more to higher E.N. atom
Electronegativity difference range = 0.3 – 1.7
(for polar covalent bonds)
Polar Covalent Bonds dissolve in water
– Why?
–
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(Check out page 19 in your packet for EN of water)
The light bulb doesn’t light up.
Non-polar Covalent Bonds
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Equal sharing of electrons
Electronegativity difference range =
0.0 – <0.3
Usually found between diatomic
molecules – two of the same atoms
Non-polar covalent bonds don’t
dissolve in water.
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Metallic Bonds
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Bond formed between 2 metal atoms.
Electrons are free to move within
electron clouds of all metal ions =
Sea of Electrons
Excellent electrical conductors in solid
state
Metallic Bonds
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In metals, p-orbitals
and some d-orbitals
are completely
vacant and overlap
each atom.
Electrons are
delocalized – they
don’t belong to any
one atom anymore.
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Quick Review

Ionic bonds are between
– A) metals and non-metals
– B) non-metals
– C) metals
Answer A) metals and non-metals
Quick Review

Covalent bonds are between
– A) metals and non-metals
– B) non-metals
– C) metals
Answer B) non-metals
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Quick Review

Metallic bonds are between
– A) metals and non-metals
– B) non-metals
– C) metals
Answer C) metals
Quick Review

The strongest bonds are between
– A) metals and non-metals
– B) non-metals
– C) metals
Answer A) metals and non-metals (ionic)
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Quick Review

Ionic bonds at room temperature are
– A) solid
– B) liquid
– C) gas
– D) any
Answer A) solid
 Can you name some?
Quick Review

Covalent bonds at room temperature are
–
–
–
–
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A) solid
B) liquid
C) gas
D) any
Answer D) any
Can you name some?
HCl (aq), Bromine (aq), Fluorine (g), Diamond
(s)
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Quick Review

Metallic bonds at room temperature are
–
–
–
–
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A) solid
B) liquid
C) gas
D) any
Answer A) solid and B) liquid
What metallic bonds can be liquid at room
temperature?
Hg Any ideas why?
Bond strength not enough to make a solid yet
strong enough to keep it from being a gas.
Quick Review

Which bonds are most likely to
dissociate in water (water is polar)
– A) ionic
– B) polar covalent
– C) nonpolar covalent
– D) Metallic
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Answer A) ionic
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