1. I. Atomic Structure II. Masses of Atoms Mass Number Isotopes Ion
Ch. 3 - Atomic Structure
I. Atomic Structure
II. Masses of Atoms
Mass Number
Isotopes
Ion

2. H Atomic Structure 1 1.00784 Proton = p+ Electron = e- Neutron = n0
Atomic # is the number at the top of each block on the periodic table
Atomic # = #p
Neutral Atom #p = #e- 1 H

3. A. Mass Number always a whole number NOT on the Periodic Table!
mass # = protons + neutrons
always a whole number
NOT on the Periodic Table!
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4. Mass # Atomic # Element Notation Hyphen notation: carbon-12
Hyphen Notation: element name – mass #
Nuclear Symbol: Mass #atomic #symbol
Hyphen notation: carbon-12
Nuclear symbol:
Mass #
Atomic #

6. Isotopes Atoms of the same element with different mass numbers.
Carbon – 12
Carbon – 14
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7. Ion – add up number of protons (+) and electrons (-)
Ion is a neutral atom that gains or loses e-
Loses e- (More protons) = (+) charge
Gains e- (More electrons) = (-) charge

8. B. Isotopes
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9. B. Isotopes Chlorine-37 17 37 20 atomic #: mass #: # of protons:
# of electrons:
# of neutrons: