Matter

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Matter The Atom
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Matter

• The term matter describes all of the physical
  substances around us your table, your body, a
  pencil, water, and so forth

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Matter

• Anything that has mass and takes up space (has
  volume)
• Includes all things that can be seen, tasted,
  smelled, or touched
• Does not include heat, sound, or light

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Matter is made of atoms
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Models

• Models are often used for things that are too
  small or too large to be observed or that are too
  difficult to be understood easily

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Models

• In the case of atoms, scientists use large models
  to explain something that is very small
• Models of the atom were used to explain data or
  facts that were gathered experimentally.
• So, these models are also theories

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Early Models of the Atom Democritus

• Universe was made of empty space and tiny bits of
  stuff
• Called these tiny bits of stuff atomos
• Atoms could not be divided

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Early Models of the Atom Lavoisier

• Demonstrated that burning wood caused no change
  in mass
• Law of Conservation of Matter

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Early Models of the Atom Dalton

• All elements are composed of indivisible
  particles.
• Atoms of the same element are the same
• Atoms of different elements are different.
• Compounds consisted of atoms of different
  elements combined together

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Early Models of the AtomThomson

• Plum pudding model
• Atom made of a positively charged material with
  the negatively charged electrons scattered
  through it.

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Early Models of the Atom Rutherford

• Mostly empty space
• Small, positive nucleus
• Contained protons
• Negative electrons scattered around the outside

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Early Models of the Atom Bohr

• Electrons move in definite orbits around the
  nucleus

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Early Models of the Atom Chadwick

• Discovered the neutron

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Modern Model of the AtomThe electron cloud

• Sometimes called the wave model
• Spherical cloud of varying density
• Varying density shows where an electron is more
  or less likely to be

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A closer look at quantum mechanics

• http//www.fearofphysics.com/Atom/atom1.html

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Atoms Family Album

• In the center of Matterville, there is a place
  called the Nucleus Arcade, where two members of
  the Atoms Family like to hang out. Perky Patty
  Proton, like her sisters, is quite large with a
  huge smile and eyes that sparkle (). Patty is
  always happy and has a very positive personality.
  Nerdy Nelda Neutron is large like Patty, but she
  has a boring, flat mouth and eyes with zero
  expression (o). Her family is very apathetic and
  neutral about everything. Patty, Nelda, and their
  sisters spend all their time at the arcade.

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Atoms Family Album

• Around the Nucleus Arcade, you will find a series
  of roadways that are used by another member of
  the Atoms Family, Enraged Elliott Electron.
  Elliott races madly around the Arcade on his
  bright red chrome plated Harley-Davidson. He
  rides so fast that no one can be sure where he is
  at any time. Elliott is much smaller than Patty
  and Nelda and he is always angry because these
  bigger relatives will not let him in the Arcade.
  He has a frown on his face, eyes that are
  squinted with anger, and a very negative (-)
  attitude.

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Atoms Family Album

• The first energy street can only hold only two
  Electron brothers. The second energy street,
  called the Energy Freeway, can hold 8 brothers.
  The third energy street, called the Energy
  Superhighway, can hold 18 of the brothers.

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Atomic Structure

• Nucleus
• Protons
• Neutrons
• Electrons

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Atomic Structure

• Electrons
• Tiny, very light particles
• Have a negative electrical charge (-)
• Move around the outside of the nucleus

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Atomic Structure

• Protons
• Much larger and heavier than electrons
• Protons have a positive charge ()
• Located in the nucleus of the atom 

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Atomic Structure

• Neutrons
• Large and heavy like protons
• Neutrons have no electrical charge
• Located in the nucleus of the atom 

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Atomic Structure
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Describing Atoms

• Atomic Number number of protons
• In a neutral atom, the of protons the of
  electrons

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Describing Atoms

• Atomic Mass Number - equal to the number of
  protons plus neutrons.

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Describing Atoms

• Atomic Weight - average mass of the naturally
  occurring isotopes of an element .