1. Chem 11

2. History Russian scientist Dmitri Mendeleev taught chemistry in terms of properties. Mid 1800 - molar masses of elements were known. Wrote down the elements in order of increasing mass. Found a pattern of repeating properties.

3. Mendeleev’s Table Grouped elements in columns by similar properties in order of increasing atomic mass. Found some inconsistencies - felt that the properties were more important than the mass, so switched order. Found some gaps. Must be undiscovered elements. Predicted their properties before they were found.

4. The modern table Elements are still grouped by properties. Similar properties are in the same column. Order is in increasing atomic number. Added a column of elements Mendeleev didn’t know about. The noble gases weren’t found because they didn’t react with anything.

5. Horizontal rows are called periods There are 7 periods

6. Vertical columns are called groups. Elements are placed in columns by similar properties. Also called families

7. Similarities Groups: vertical columns –Have similar properties because they have same number of electrons in outer shell

8. 1A 2A3A4A5A6A 7A 8A The elements in the A groups are called the representative elements

9. The group B are called the transition metals u These are called the inner transition elements and they belong here

10. Group 1 are the alkali metals Group 2 are the alkaline earth metals

11. Group 7A is called the Halogens Group 8A are the noble gases

12. Metals: To the left of the staircase line Physical Properties:  Luster (shiny)  Good conductors  High density  High melting point  Malleable Chemical Properties:  Easily lose electrons  Corrode easily (ex: rusting or tarnishing)  Low electronegativity

14. Non metals: to the right of the staircase line Physical Properties:  Dull  Poor conductor  Brittle  Not malleable  Low density and melting point Chemical Properties:  Tend to gain electrons  High electronegativity

15. Metalloids: along the staircase line Solids Shiny or dull Malleable Conduct heat and electricity better than non metal but not as well as metals

16. Colour your periodic table Draw the staircase in with a dark line Put the group numbers (A and B) at the top of each group Metals = 1 st color Metalloids = 2 nd color Non-metals = 3 rd color *Periodic table in the back of the book is colored this way!