Transcript OCTOBER 8, 2013

OCTOBER 8, 2013
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Turn in your homework if you have it. Lab Sheet
and Measuring Matter due tomorrow!!
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Date your journal. Title: Atomic Structure
ATOMIC THEORY TIMELINE
SIGNIFICANT CONTRIBUTIONS
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1803
Dalton
1904
JJ Thomson
Plum pudding
1911 Rutherford
1913 Bohr
NUCLEAR MODEL OF THE ATOM
A conceptual model of the atom in which a small
positively-charged nucleus is surrounded by
planetary electrons
LOCATIONS IN THE ATOM
ATOM HAS TWO LOCATIONS:
1.
NUCLEUS
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2.
Small Center of the Atom
Made of Protons and Neutrons
Mass of the Atom
Positively Charged
ELECTRON CLOUD
- Surrounds the Nucleus
- Mostly empty space
- Where electrons orbit the nucleus
- The cloud is huge, the electrons are tiny
- The electron cloud has areas where electrons are more likely to be
found and areas where they are less likely to be found
PICTURE THIS…..
A football stadium, which represents the atom
The nucleus would be in the center on the 50 yd
line, but the protons and neutrons that make
up the nucleus would be about the size of
sesame seeds. Almost all of the mass is here!!
The rest of the stadium would be the electron
cloud, but the electrons would not be able to be
seen if the atom were the size of a football
stadium. Atoms are mostly empty space!!!!
PROTONS (+)
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Positively charged
particles
Help make up the
nucleus of the atom
Help identify the atom
(could be considered an
atom’s DNA)
Equal to the atomic
number of the atom
Contribute to the
atomic mass
Equal to the number of
electrons
-
++ +
+ ++
+ +
-
-
+
-
NEUTRONS
-
++ +
+ ++
+ +
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-
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-
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Neutral particles;
have no electric
charge
Help make up the
nucleus of the
atom
Contribute to the
atomic mass
ELECTRONS (-)
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Negatively charged particles
Found outside the nucleus of
the atom, in the electron
orbits/levels (rings) 2 – 8 - 8
Move so rapidly around the
nucleus that they create an
electron cloud
Mass is insignificant when
compared to protons and
neutrons (mass is negligible)
Equal to the number of
protons
Involved in the formation of
chemical bonds
-
++ +
+ ++
+ +
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SUBATOMIC PARTICLES
Particles that are smaller than the atom
PROTONS (p+) in nucleus
NEUTRONS (no ) in nucleus
ELECTRONS (e -) in electron cloud