Download A. Highlights for Section 1 pages 83

Matter: Building Blocks of Universe
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Atoms: Building Blocks of Matter
Highlights
A. Highlights for Section 1 pages 83-90
 Related indirect evidence to the steps involved in the
developments of a model of an atom
o 2400 years ago scientists did not have technology for
direct evidence
o Scientists used indirect evidence about an object
without seeing or touching the object
 Describe the changes of the Atomic Model
o Greek Model (Democritus)
Smallest – atom - cannot be subdivided
o Dalton Model (Dalton)
Elements made of atoms – atoms invisible
Atoms of same element alike
Compounds formed by atoms
o Thomson Model (Thomson)
Positive and Negative charges
o Rutherford Model (Rutherford
Positive particles in nucleus
Negative particles outside of nucleus
o Bohr Model (Bohr)
Negative particles – electrons – orbits
o Wave Model (Present Day)
Wave mechanics
Smallest “+” Nucleus make atom neutral
Larger “-” Obits
G. Highlights for Section 2 pages 92-99
 Classify three main subatomic particles
o Proton
In nucleus
Positive charge
1 AMU
o Neutron
In nucleus
No charge
less than 1 AMU-smaller than proton
o Electrons
In orbit around nucleus
Negative charge
No mass (AMU) or very little
 Explain the structure
o Atomic number=number of protons
o Mass number=sum of protons & neutrons
o Isotopes=difference between number of neutrons to
protons
o Electron clouds=space around nucleus contains
electrons – has energy levels
o Quarks=splitting of subatomic particles
M. Highlights for Section 3 pages 99-101
 Identify four forces associated with atomic
structure
o Electromagnetic
Attract: Opposite charges attract, same
charges repel
Keeps electrons in orbit
o Strong
Opposes electromagnetic force or
repulsion between protons – glues protons
together
o Weak
Responsible for radioactive decay
o Gravity
Weakest force