Atomic BondingPage 12

Valence Electrons

Outer most shell of electronsHeld loosely to an atom

Key to all chemistryAll atoms want to have full shells

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Electron Dot Diagrams

Use the symbol for each element with a dot for each outer electron.

Identify each element and the number of valence electrons that it has.

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H C OHydrogen 1

Carbon 4

Oxygen 6

Magic game of

Bonding

I (At #53) has how many valence electrons?

What will it do to fill its shells?

Mg (At #12) has how many valence electrons?

What will it do to fill its shells?

Atoms always to the easiest thing!Mg will always lose 2 electrons never gain 6

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7Gain 1 electron

2

Gain 6 or lose 2 electrons

Bonding

Where do extra electrons go?Where can atoms find the electrons they

need?Atoms trade electrons = Chemical bond

*The fewer electrons you need to trade the more reactive the atom will be!

When atoms bond, new substances are made.

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Review

How are element represented in the periodic table?

By symbolThe ____________ of an element is the

number of protons in the nucleus of the atom

What is a row of elements across the table called?

PeriodDescribe how the atomic number changes

across a period of elements.Each element increases by 1 atomic

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atomic number

Review

What are the elements in the same column called?

Group or familyElements within a group always have the same number

of

Valence Electrons

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Nonmetals

How many valence electrons do non-metals have

4 or moreDescribe two ways that non-metals can

combine with other elements.Combine with metals to gain electronsCombine with other non-metals to share electrons

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