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

2. Elements and atoms
Elements on the periodic table are made of atoms.
Atoms are the smallest form of matter.
All atoms in an element look the same.
The structure of an atom determines how that atom will react with other atoms of a different element
Atom: Element: 8 O

3. Atomic Structure & Atomic Number
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

4. Atomic Mass (Mass Number) – the number of particles in the nucleus of a single atom
Atomic Mass= protons + neutrons
always a whole number
NOT on the Periodic Table!
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5. Naming a single atom is called atom notation
Each element has billions of atoms so it is important to name each one correctly.
Naming a single atom is called atom notation

6. Mass # Atomic # Atom Notation Hyphen notation: carbon-12
1. Nuclear Symbol: Mass #atomic #symbol 2. Hyphen Notation: element name – mass #
Hyphen notation: carbon-12
Nuclear symbol:
Mass #
Atomic #

7. Atom Notation - Name this atom using both forms of notation
REMEMEBER!!!
# p = atomic #
Mass # = #p + #n
Hyphen Notation:
Oxygen – 16
Nuclear Symbol: O 16 8

8. Identifying parts of an atom from the atom notation17 37 20
Chlorine-37
atomic #:
mass #:
# of protons:
# of electrons:
# of neutrons:

9. Neutral Atom Remember: Neutral = same number of (+) and (-)
Neutral Atom = same number of p+ and e-
Atoms are not always neutral. Sometimes e-move around – this causes and atom to become an ion.

10. Ion – an atom that gains or loses e-, causing the atom to be charged
An atom with an unequal amount of p+ and e- causes a charge to form
Loses e- (More protons) = (+) charge
Gains e- (More electrons) = (-) charge
The quantity of the electrons lost or gained determines the charge quantity

11. Identify as a neutral atom or an ion

12. Name the ion
An ion can only be named using the nuclear symbol or if the picture is given.
Nuclear Symbol:
You cannot identify an ion or name an ion by hyphen notation. 19 F -1 9

13. Ion notation – is only identified in nuclear symbol or picture8 16 10
Oxygen - 16
atomic #:
mass #:
# of protons:
# of electrons:
# of neutrons: -2

14. Journey into an Atom
Read the introduction – pay attention to the Bean Key on the front page.
Collect the data from each atom (bag of beans) on the lab table.
Use this data to determine both types of atom notation.
Do not worry about electrical charge at the moment.

15. PEN Table – with ions
Collect a periodic table from the front table in the pink folder.
Use the periodic table to help you fill in the PEN table.
Remember to pay attention: Is it a neutral atoms or ion

16. Isotopes - Atoms of the same element with different mass numbers.
Carbon – Carbon – 14
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17. Isotopes
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