Download CHAPTER 4 ATOMIC STRUCTURE

CHAPTER 4 ATOMIC STRUCTURE
• Aristotle (Greek)
• Thought all substances were built from either fire, earth, air,
water
• Thought that atoms of a _________are smooth and round
• Thought atoms of a _________were rough and prickly
• Dalton’s Atomic Theory (1766)
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Evidence for atoms
Measured the masses of elements
Compounds have ________composition
All matter is made up of ____________particles called______,
which cannot be divided
• 1 All _________are composed of ______
• 2 All atoms of the same element have the____ ______, and atoms of
different elements have different masses
• 3 ___________contain atoms of more than 1 element
• 4 in a particular compound, atoms of different elements always
________the same way
• Evidence for subatomic particles
– _______and _______are spread throughout the atom
– Earnest Rutherford- (1871-1937)
• Alpha particles---_____ moving _________charged
• All the atoms _________charge is in the _________
• The nucleus is the _____________charged mass located in the center of the
atom
• Ques.1-5 pg. 105
SECTION 4-2
• Properties of subatomic particles
• Protons-- + charged particles, varies among elements
• Each nucleus contains at least _____positively charged particle
• +charge = _______
• Electron
• - charge 1• Found ________the nucleus in an _________cloud or (shell)
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Neutron
_________
Found in the ________
Mass almost = to a proton
Protons, electrons and neutrons can be distinguished by_____,
___________in an atom and the charge
ATOMIC NUMBER AD MASS NUMBER
• The atoms of any element contain the _______number of
protons
• Example there is one proton in the nucleus of every hydrogen
atom. There hydrogen has an atomic number of 1
• ATOMIC NUMBER = _________________________
• Atoms of __________elements have different numbers of
protons
• Sulfur= atomic #= 16 because it has 16 protons in the nucleus
• Each ________charge is balanced by a ________charge SO
hydrogen has ___ proton and ____ electron sulfur __ protons
and ___ electrons
• MASS NUMBER= the ______of the _______and ________in
the nucleus of the atom
• Ex Aluminum= 13 protons+14 neutrons= an atomic mass of 27
• Number of neutrons= ______ _ _______
• Ex. Aluminum 27-13= 14 (#of neutrons)
ISOTOPES
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When an atom does not have the same ________of neutrons
Same atomic number but different mass #’s
Ex. Oxygen-16, 17, and 18
All oxygen atoms have 8 protons, but some have 9 or 10
neutrons
• Ques. 1-7 pg. 112
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Energy levels
1 one orbital max __ electrons
2 four orbitals max ___ electrons
3 nine orbitals max ___electrons
4 sixteen orbitals max ___ electrons
• Electron configuration—arraignment of _________in the
orbitals of an atom
• _______levels get filled before higher energy levels----inner to
outer
• Stable electron configuration is the one in which the electrons
are in orbitals with the ______possible energies (ground state)
• Ques. 1-5 pg. 118
4-3 Modern Atomic Theory
• Niels Bohr-1885-1962 Danish physicist focused on electrons in
the electron cloud
• Energy levels
• Each _________has a _____amount of energy
• Electrons closer to the nucleus have ____energy than further
away from the nucleus
• They move in a less than predicable way
• Atomic orbitals
– The electron cloud represents ___the orbitals in an atom
– An orbital is a region of space around the_______ figure 15 page 117
(copy into notes)
– Draw in your notes the Thomson, Rutherford, Bohr, and electron cloud
models (pg 115)
• An ________in an atom can move _______energy levels when
the atoms gain or ____energy
• The ____of the jump between orbitals determines the amount of
energy ______or ____
• Evidence for movement from one level to another is _____--light is a form of ______-----heat is another cause of ________of
electrons from one orbital to another
• Electron cloud-how electrons behave in their orbitals
• Electrons move like _______in the solar system around the_______, they move
in a less than predicable way
• When electrons move to a ______energy level they are
considered in an _______state
• Ex. He, Ne, Ar Kr, Xe find out the names of these elements