Review:
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molecular compounds
ionic compounds
naming compounds
prefixes
trivial names
Sep 13­12:50 PM
Energy Level Diagrams
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energy level diagrams can be drawn for both elements and ions
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elements are neutral while ions have a charge
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ions are created from elements by adding or subtracting electrons
Ex:
Mg2+
Mg
Sep 13­12:54 PM
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­ ions carry a charge but have a full valence shell
­ group number of an element is the number above the vertical column of the periodic table, indicates an elements valency (number of electrons in the outer energy level)
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period number is the horizontal row of the periodic table which tells how many energy levels an atom has
Ex.
Oxygen
Sep 13­12:59 PM
Copy and Complete:
Element Valence Electrons Energy Levels Calcium
Carbon
Sodium
Argon
Boron
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what do you notice about argon versus the other elements?
Sep 13­1:03 PM
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argon is a noble gas, they all have full shells of electrons
Ex.
Draw energy level diagram for neon
­ most elements want to become stable, hence they gain or lose electrons to look like their nearest noble gas
­ Octet rule: atoms gain or lose electrons to become stable (get the same structure as the noble gases)
Sep 13­1:10 PM
Rules for Drawing Energy Level Diagrams for Ions
1. Atoms with 1,2 or 3 valence electrons lose them to form 1+, 2+ or 3+ ions
2. Atoms with 5,6, or 7 electrons gain electrons to form 3­, 2­ or 1­ ions
3. Atoms with valance four do not usually form ions
Sep 13­1:17 PM
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Draw the Energy Level Diagrams
a. sulphur
b. sulphur ion
c. aluminum
d. aluminum ion
Sep 13­1:22 PM
Naming Ions
­ to name a positive ion you use the element name + ion
Ex.
Ca2+ Calcium Ion
K+
Potassium Ion
­ to name a negative ion use the element name with an ide ending
Ex.
Cl­
O2­
Chloride
Oxide
Sep 13­1:24 PM
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Readings:
Pages 184­186
Activities:
Complete the worksheet provided
Sep 13­1:27 PM
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