Structure of the Atom

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Structure of the Atom
Chapter 10 Pages 240 - 254
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How are atoms studied?

• Atoms are the building blocks of matter
• Atoms are too small in size to study easily
• Size of Earth soda can soda can atom

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Who studied the atom?

• Studied by many scientists for centuries
• Democritus (400 BC) phrase atomos
• Rutherford (1911) nucleus (gold foil expt)
• Moseley (1913) X-rays to find atomic
• Bohr (1913) planetary model of the atom
• Schrödinger (1923) electron cloud model

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The Bohr Model
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Im an electron!
Im a proton!
Im a neutron!
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I was walking along and I saw these two.
I was telling jokes to the neutron.
The proton and I were having fun.
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They looked so happy there together.
I was p o s i t i v e l y charged!
I couldnt have amassed more happiness.
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The proton looked happy, so I wandered closer.
I could see the electron coming near.
The who? Huh?
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They were HUGE next to me!
The electron was so cute!
Like a speck of dust, or something
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I didnt want to seem obvious, so I kept walking.
Around and around the electron goes.
Hey electron, youre making the proton dizzy.
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The proton seems so happy with the neutron.
Im having fun, but I still notice the electron.
It wont bother me if the electron hangs around.
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I guess Ill just wander around out here.
Im happy hanging out here.
The center is cool, but sometimes it can be a
Bohr.
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Electrons circle around the nucleus of an atom.
Protons are a main part of the nucleus of an atom.
Neutrons also hang out in the nucleus of an atom.
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Electrons have a negative charge. ?
Protons have a positive charge.
Neutrons have no charge. 0
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Electrons are little and have a mass of almost
zero.
Protons are big and have a mass of one.
Neutrons are also big and have a mass of one.
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The Bohr Model
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What is the structure of an atom?

• Nucleus center of the atom
• Home of Protons and Neutrons
• Proton
• Has a positive () charge
• Has a relative mass of 1
• Determines the atomic number
• Found inside the nucleus

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What is the structure of an atom?

• Neutron
• Has no (0) charge
• Has a relative mass of 1
• Determines the isotope
• Isotopes are two of the same element with
  different masses
• Found inside the nucleus

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What is the structure of an atom?

• Electron
• Has a negative (-) charge
• Has a relative mass of 0 (zero)
• Determines the ion
• Found outside the nucleus
• Bohr model electrons are in specific energy
  levels
• Electron cloud model electrons are in a random
  cloud

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What is the structure of an atom?
Bohr Model Planetary Model
Schrödinger Model Electron Cloud Model
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How are P, N, e- related?

• protons atomic number
• electrons protons in a neutral atom
• protons neutrons atomic mass

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What is a chemical symbol?

• Chemical symbol tells us what atom it is
• Always a CAPITAL LETTER, sometimes followed by a
  lower case letter
• Ex Oxygen O Nitrogen N Sodium Na
• Cobalt Co Carbon Monoxide CO
• (Co is an element, CO is a compound)