1. Introduction to Mendeleev’s Periodic Table of Elements
Mrs. Coyle

2. “The Elements” Song by Tom Lehrer

3. Organizing Information
What criteria can be used?
Activity “Organizing Cards”

4. How are days organized?

5. Dmitri Mendeleev Russian 1860’s
The Person Who Organized the Elements
Dmitri Mendeleev Russian 1860’s

6. Mendeleev Teacher at St. Petersburg University.
Was working on a textbook for his Chemistry students.
He organized the 63 elements known at the time.

7. His Criteria
Increasing atomic mass.
Physical and Chemical Properties.

8. Sodium’s Reaction with H2O

9. Potassium’s Reaction with H2O

10. Periodicity
Reoccurrence (repetition) of properties at regular intervals.

11. Mendeleev’s Periodic Table

12. Like A Calendar

13. Mendeleev’s Predictions
He left spaces on the table for undiscovered elements.
He predicted the properties of elements that had not yet been discovered.
How?

14. Example: Eka-aluminum
He placed this undiscovered element below aluminum.
He predicted the melting point to be low and the density to be 5.9g/cm3.
It was later found and named Gallium with a density of 5.91g/cm3 and melting point of 29.7oC.

15. Gallium

16. A brief comparison of the modern periodic table to Mendeleev’s
What is the main criterion used to organize elements in the modern periodic table?

18. Recap
Mendeleev’s Criteria
Periodicity
Prediction