CHEMISTRY!!!

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CHEMISTRY!!!

• Yeah baby!

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Structure of the Atom

• Nucleus The center of an atom. Holds the protons
  and neutrons.

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Structure of the Atom

• Protons Positive charge, atomic number
• Neutrons no charge
• Both found in the Nucleus!

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Structure of the Atom

• Electrons Negative charge, orbit the nucleus

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Structure of the Atom

• Atoms on the periodic table have 2 numbers

Atomic mass
9 Be 4
Atomic number
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Structure of the Atom

• Atomic mass mass of both the neutrons and
  protons.
• Protons 1
• Neutrons 1

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Structure of the Atom

• Atomic number Number of protons
• Protons tell you what atom it is!

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Structure of the Atom

• Isotopes When the number of neutrons differ,
  changing the atomic mass, BUT atomic number stays
  the same!

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Structure of the Atom

• Carbon

13 C 6
12 C 6
14 C 6
15 C 6
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Electron shell

• Shells
• 1st shell 2 electrons
• 2nd shell 8 electrons

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Electron shell

• Complete Shell no empty sites, full electron
  count in shell.

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Element vs. Compound

• Element same kind of atom
• Compound made up of mixed elements

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Chemical Bonding

• There are three types of major bonds
• Ionic
• Covalent
• Hydrogen

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Chemical Bonding

• The bonds are determined by differences in
  electronegativity (power of an atom to attract
  electrons).

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Chemical Bonding

• Ionic Atom Gives (takes) an electron from
  another atom and then becomes shell complete.

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Chemical Bonding

• Ionic One becomes positively charged and one
  becomes negatively charged.
• (Electroneg is 1.7)

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• Na
• Cl
• Na-Cl

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Chemical Bonding

• Covalent 2 atoms share an electron to become
  shell complete. It is a stronger bond then Ionic.
• (Electroneg is 1.6)

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• H
• O
• H-O-H

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Chemical Bonding

• Hydrogen Bond Bond formed when hydrogen is in
  covalent bond with another element, because of
  unequal sharing of electrons.

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Chemical Bonding

• Hydrogen Bond Atoms become polar with Hydrogen
  side having a slight positive side. Allowing a
  weak bond with negative ion.

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Practice

• Worksheet.

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Some Atoms are Sociable, Others Arent
Atoms want (are most stable) to have a filled
outer electron shell.
Atoms without a filled outer shell will share
electrons with other atoms to accomplish this
goal.
Filling outer electron shells controls which atom
will pair with which others and in what
combinations.
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Filling Electron Shells
An important rule the innermost shell holds two
electrons subsequent shells hold 8 electrons.
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Pairing for the Greater Good
When atoms come together by sharing electrons the
bond is a covalent bond.
H2
A molecule is formed when two or more atoms are
bound together covalently.