Chemical Formulas

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Chemical Formulas

• Unit 7

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Ions

• Ion a charged atom or molecule.
• Ions can be
• positive (cations) electrons lost
• negative (anions) electrons gained

3
0
1
2
4
-3
-2
-1
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SKIP
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Forming Ions

• Ion Formation An ion forms when an atom gains
  or loses electrons to become more stable.
• They want 8 valence electrons.

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Diagrams of ion formation

• Ca atom becomes Ca2 ion
• N atom becomes N3- ion

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Element symbol for original atom Symbol for ion formed Loss or gain of electrons? of electrons lost/gained Cation or anion?
Mg Mg 2
Br Br -
Al Al 3
O O 2-
loss
2
cation
gain
anion
1
loss
cation
3
anion
gain
2
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Nonmetals
Metalloids
Metals
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Do the following

• Go get four sheets of paper.
• AT LEAST TWO MUST BE WHITE!
• Sit back down!
• Get out your Flip Card notes.

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Fold and staple
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Glue on labels
Chemical Formulas Period ____ Your name (put
yours)
Extra Notes
Definitions
Ionic Compounds
Transition Metals (Roman Numerals)
Compounds with Polyatomic Ions
Covalent (Molecular) Compounds
Acids and Bases
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Glue

• Polyatomic Ion sheet on the back!