Ionic bonds

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9.18 WARM UP
1. How do elements combine to
form compounds?
2. What do ionic bonds mean?
3. What do covalent bonds mean?
Announcements
Quiz Friday: atomic theory, atomic
structure, bonding
SF: 12 journal entries, data table
outline, & typed hard copy of
Experimental Design
Learning Goal: Structure of Matter
• 4 – I can describe the properties of matter and
predict ways that the atoms bond
• 3 – I can describe the properties of matter and
identify bonds
• 2 – I can describe the properties of matter
• 1 – I need to review
Review Atoms
• Outer shell has the
_________ e• The inner shells are
complete and stable
• Elements are organized
by # of valence e• # of valence edetermines properties
and how it reacts with
other elements
Chemical Bonds & Stability
• Due to charges, atoms
tend to become stable.
• Atoms with full shells
are stable
• Atoms with 8 e- or 2 ein outer shell are stable
and tend to not react
with others
Chemical Bonds & Stability
• Atoms react to
become more stable
– Lose e- to get to 8
– Gain e- to get to 8
• Chemical Bond = the
force of attraction
that holds two
atoms together as a
result of the
rearrangement of ebetween them
•
•
•
•
•
•
Ionic Bonds
Ionic bonds = the transfer of electrons
Atoms with 5, 6, or 7 e- tend to gain
Atoms with 1,2 or 3 e- tend to lose
Ions = charged atoms
Cation = + charge (lost e-)
Anion = - charge (gained e-)
Sodium & Chlorine
• http://www.middleschoolchemistry.com/multimedia/chapter
4/lesson5#ionic_bond_in_sodium_chloride
Properties of Ionic Bonds
• Hard, brittle crystals
• High melting points
• Conduct electricity when
dissolved in water or
melted
• Usually formed with a
metal and nonmetal
atom
Atoms are lonely hearts that are constantly in search of partners
to bring stability to their lives. Your job is to play matchmaker
and make each atom stable by determining how many valence eeach element needs & finding a partner that will complete the
valence energy level!
Bachelor #1, Mr. Sodium
• Mr. Sodium is very
lustrous but watch out,
he has an explosive
personality when he gets
near water or oxygen.
• He is quite a lonely metal
and like most metals is
looking to lose a few
electrons!
• Since he is highly reactive,
be careful who you pick
to be his date!
11
Na
Sodium
22
• Ms. Lithium over here is
quite a catch. She’s a bit
feisty , especially
around water and
oxygen. She, too is
looking to lose
electrons
• Ms. Fluorine, she can
light up any place! She
is a non metal and is
looking to gain
electrons.
3
9
Li
F
Lithium
7
Fluorine
19
Next Contestant
• Ms. Chlorine, hard to
catch and rarely found
on her own but she’s
now looking to settle
down and find someone
to make her a little
more stable.
17
Cl
Chlorine
35
Eligible Bachelors
• Sr. Potassium, also
known as Mr. K, puts off•
a rough side initially but
calms down when
paired up with a
reactive mate!
Mr. Barium, commonly
know as the Big B, has
an incredible atomic
mass weighing in at 137
amu. He over time will
become reactive to not
only water but also air.
19
56
K
Ba
Potassium
39
Barium
137
Covalent Bonds
• Covalent = sharing e• Usually form between atoms of nonmetals
• Atom’s nucleus is the force that holds the
atoms together
Covalent Bonds
Covalent Bonds
• Water
• http://www.middleschoolchemistry.com/multimedia/chapter
4/lesson4#covalent_bond_hydrogen_animation
•
More Covalent Bonds
Methane
• CH4
H
C
Properties of Covalent Bonds
•
•
•
•
Molecular Compounds
Lower melting points
Lower boiling points
Do not conduct electricity when dissolved in
water
Review
Transferring e= ionic
Sharing e= covalent
Atomic Game
• Follow the hand outs to complete the
appropriate activities
• You will have 8 minutes at each table, watch
the clock
• Table captains – in relation to the table
number & your original seat number
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