1. The Periodic Table & Atomic Structure
2.1

2. CHAPTER 6
Matter is made of atoms and every element has its own unique type of atom.
Elements are identified by names and chemical symbols.
Atoms have a structure that determines their properties.
Every atom is composed of three types of subatomic particles: protons, neutrons, and electrons.
The number of electrons in the outer shell of an element’s atoms determines the properties of the element.
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3. 6 The Periodic Table organizes elements in different ways.
CHAPTER 6
The Periodic Table organizes elements in different ways.
Metals are found on the left, non-metals on the right, and metalloids in between.
Chemical families are arranged in vertical groups.
Periodic Tables can indicate the chemical symbol, atomic number, atomic mass, ion charge, density, and other information about each element.
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4. Elements are listed in order by atomic number
Rows of elements (across) are called periods.
All elements in a family have similar properties, and bond with other elements in similar ways
Group 1 = alkali metals
Group 2 = alkaline earth metals
Group 17 = the halogens
Group 18 = noble gases
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5. CHAPTER 6
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6. 6.1
VOCABULARY
physical properties
chemical properties
mixtures
pure substances
elements
atoms
compounds
Physical properties can be observed without changing the chemical structure of a substance.
Chemical properties describe a possible chemical change.
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7. 6.2
The Nucleus
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8. Atomic Theory VOCABULARY Ch. 2 subatomic particles nucleus protons
neutrons
atomic number
mass number
atomic mass
electrons
electron shells
unpaired electrons
paired electrons
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9. area surrounding the nucleus
Atomic Theory
Name
Symbol
Charge
Location
Relative Mass
Proton p 1+
nucleus
1836
Neutron n
Electron e 1–
area surrounding the nucleus 1
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10. 6.2 Every atom of any one element will have the same number of protons
Atomic number = # of protons = # of electrons
There are an equal number of protons and electrons in an atom.
Ions form when the number of electrons changes.
The number of electrons in the outer shell determines the properties of the element.
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11. Bohr Diagrams
Bohr diagrams show how many electrons appear in each electron shell around an atom.
Each shell holds a maximum number of electrons
2 electrons in the first shell, 8 in the 2nd shell, and 8 in the 3rd shell.
Electrons in the outermost shell are called valence electrons
Think of the shells as being 3D like spheres, not 2D like circles
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12. The period # = # of shells in the atom.
Except for the transition elements,
the last digit of the group # = # of electrons in the valence shell
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13. Bohr Diagrams
What element is this?
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14. Bohr Diagrams
18 p
22 n
Argon!
It has = 18 electrons, and therefore 18 protons
It has 3 electron shells, so it is in period 3
It has 8 electrons in the outer (valence) shell
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15. Patterns of Electron Arrangement in Periods and Groups
The noble gas elements have full electron shells, and are very stable.
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16. The Periodic Table Ch. 2 Where are the following? Atomic Number Period
INCREASING REACTIVITY
Where are the following?
Atomic Number
Period
Group/Family
Metals
Non-metals
Transition metals
Metalloids
Alkali metals
Alkaline earth metals
Halogens
Noble gases
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