1. The Periodic Table Periodic Properties of Elements
Periodic Law
The Periodic Table
Periodic Properties of Elements

2. Development of the Periodic Table-Mendeleev
Dmitri Mendeleev
Studied elements
Grouped elements with similar properties together
Arranged elements in order of increasing atomic mass

3. Mendeleev

4. Development of the Periodic Table-Modern
Modern Periodic Table
Henry Mosely determined atomic numbers of the elements
Elements are now arranged in order of increasing atomic number.

5. Atomic number
Atomic mass

6. Development of the Periodic Table-Terms
Columns of the periodic table are called groups or families
Rows of the periodic table are called periods
Periodic law states that the physical and chemical properties of the elements are periodic functions of their atomic numbers.

7. Modern Periodic Table

8. Periodic Properties: Metals, Nonmetals and Metalloids
Metals give up electrons easily. They are found on the left side of the periodic table
Nonmetals have a tendency to gain electrons. They are on the right side.
Metalloids are found on the zigzag line between metals and nonmetals.

9. Metals Nonmetals

10. Properties of Metals Shiny Ductile Malleable Give up electrons easily
Good conductors of heat and electricity
sodium
copper
mercury

11. Properties of nonmetals
Dull
Brittle
Nonconductors
Usually gases or liquids at room temperature
bromine
sulfur

12. Periodicity Elements vary in a regular way across the table. Examples:
Valence number
Reactivity
Ionization energy
Atomic size
Melting and boiling points

13. Periodicity: Valence numbers
Valence electrons are shown in red
(note: transition elements not shown in this table)

14. Periodicity: chemical reactivity of elements
most reactive
least
reactive
most reactive

15. Periodicity: atomic radii