1. The Periodic Table
Use the periodic table to determine the number of protons, neutrons, and electrons in an isotope of an element.
Use the periodic table to identify the characteristics and properties of metals, non-metals, and metalloids.

2. Mendeleev Russian chemist in 1860s
Arranged elements in rows with similar properties and increasing mass
Left blanks for undiscovered elements

3. Modern Periodic Table Elements arranged by atomic number
Periods-rows across the table
Groups-columns (also called family)
Periodic Law-pattern of repeating properties

4. Classes of Elements Metals Nonmetals Metalloids
Majority of elements
Left side of the table
Transition metals
Middle of the table
Nonmetals
Only 17 elements
Right side of the table
Metalloids
Share properties of metals and nonmetals
Stair step between metals and nonmetals
Left to right, elements become less metallic and more nonmetallic

5. Alkali Metals Alkaline Earth
Group 1 A
Found only in compounds in nature
Reactivity increases as you go down the row
Have only 1 valence electron
Li, Na, K, Rb, Cs, Fr
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Group 2 A
Harder than Alkali Metals
Reactivity increases as you go down the row
Have only 2 valence electron
Be, Mg, Ca, Sr, Ba, Ra

6. Transition Metals Lanthanides and Actinides Found in the middle
Make colored compounds
Found at the bottom
Many radioactive and man-made
Called rare earth metals

7. Boron Carbon Nitrogen Oxygen Group 4A Group 3A 4 valence electrons
B, Al, Ga, In, Tl
Group 4A
4 valence electrons
C, Si, Ge, Sn, Pb
Nitrogen Oxygen
Group 5A
5 valence electrons
N, P, As, Sb, Bi
Group 6A
6 valence electrons
O, S, Se, Te, Po

8. Halogens Noble Gases Group 7A Group 8A 7 valence electrons
React easily with metals
F, Cl, Br, I, At
Group 8A
8 valence electrons
Extremely unreactive
Colorless, odorless
He, Ne, Ar, Kr, Xe, Rn