1. Unit 6, Lesson 5: Mendeleev and the Periodic Table

2. Video Questions
In early periodic tables, what property was used to order the elements?
How did Mendeleev change the early periodic tables to make his version?
What property is used to order the elements in the modern periodic table?
Why was Mendeleev’s periodic table significant?

3. Mendeleev and the Periodic Table
15 min

4. Answers to Video Questions
Atomic mass was used at first.
He arranged elements into periods according to their properties.
Atomic number is now used.
It allowed him to predict the properties of undiscovered elements, and led to many important discoveries by other chemists, who wanted to know why the periodic table worked so well!

5. Brain Break!

6. Step into Mendeleev’s shoes!
Form a group of three. Obtain a set of element cards.
Try to arrange the cards into a periodic table based on the properties of the elements.
Once you have a table that follows a logical sequence, use the patterns in your table to predict the properties of “Phorgum”.
Show Ms. Bartz when you are finished!
20 min