2ChemCatalystIn 1889 a Russian chemistry teacher created an organized table of the elements. At the time only 63 different elements were known. Below is a reproduction of that table.What do you think the numbers represent?(cont.)
4The Big QuestionHow did Mendeleyev organize the elements?
5You will be able to:Explain how the periodic table of elements is organized.
6NotesDimitri Mendeleyev is credited with organizing the elements into the first periodic table.The main properties that Mendeleyev used to sort the elements were reactivity with one another and a number describing the atomic weight of each element.
7ActivityPurpose: The goal of this lesson is to acquaint you with Mendeleyev’s organization of the elements by allowing you to create your own table from the patterns you see in the elements.
8Making SenseBelow are five possible cards for the element germanium. Where does germanium belong in the table? Which card seems most accurate to you? What is your reasoning?(cont.)
9C A B (cont.) D E Ge 62.7 Ge 62.7 Ge 66.0 Ge 72.6 Ge 72.6 Germanium
10(cont.)What would you add to the three empty corners to complete the card?GermaniumGe(cont.)
12Check-InWhich of the following elements would you find in the same group on the periodic table? Explain your thinking.Cadmium CdModerately soft, silvery solid, metalReact very slowly with waterFound in CdCl2 (s)Zinc ZnModerately hard, silvery solid, metalReacts very slowly with waterFound in ZnCl2 (s)Iodine IPurple solid, nonmetalReacts slowly with metalsFound in ICl (s)Mercury HgSilvery liquid, metalDoes not react with waterFound in HgCl2 (s)
13Wrap-UpMendeleyev organized the periodic table based on the properties of the elements.Mendeleyev’s arrangement of the elements helped to predict the existence of undiscovered elements.