1. Elements and The Periodic Table

3. The “Super 7” Diatomic Elements
“I Have No Bright Or Clever Friends”
HOFBrICl

4. chlorine pure substance element (molecule) water compound soil mixture
Pure substance or mixture
Element or compound heterogeneous or homogeneous
chlorine
pure substance
element (molecule)
water
compound
soil
mixture
heterogeneous
sugar water
homogeneous
oxygen
air
carbon dioxide
cookie dough
propane
iron
element (atom)

5. History of the Periodic Table
330 B.C - 4 elements
elements
elements
Chemists required a systematic method to organize the elements

6. John Newlands
1864
Arranged all known elements in order of increasing atomic mass
Observed that every 8th element had similar physical and chemical properties (Law of Octaves)
Began to group these elements into “families”

7. Lothar Meyer
1865
Also arranged the elements in order of increasing atomic mass
Found repeating patterns and developed a table of elements

8. Dimitri Mendeleev 1869 Noticed same patterns as Newlands & Meyer
Because Mendeleev published his table first, he is credited as the Father of the Periodic Table
Now, elements are not arranged by atomic mass…
Periodic Law: When arranged by atomic number, the properties of the elements repeat at regular intervals.

9. Amazing!

10. Within YOUR Lifetime

13. Horizontal stripes on nonmetals
Vertical Stripes on metalloids

14. and the same number of valence electrons

16. Hydrogen (A class of it’s own)
Sometimes it behaves like an alkali metal, sometimes like a halogen, and sometimes in its own unique way.

17. Group 1: Alkali Metals
1 valence electron (electrons in their outermost shell)
Soft, shiny, easily cut with a knife
The most reactive metals
React violently with water (stored in oil or a vacuum)
React with halogens to form salts
Never found as free elements in nature, always bonded with other elements
Braniac: alkali metals
Disposal of sodium 1947

18. Group 2: Alkaline Earth Metals
2 valence electrons
Light, reactive metals
Form oxides when exposed to air. React with oxygen to from oxides, react with hydrogen to form hydrides (except beryllium). React with water to liberate hydrogen

19. Groups 3-12: Transition Metals
1 or 2 valence electrons
Strong, hard metals
Good conductors of heat and electricity
Wide range of chemical and physical properties

20. Group 17: Halogens 7 valence electrons Extremely reactive nonmetals
Not lustrous, nonconductors of electricity

21. Group 18: Noble Gases
Full outer shell
Extremely unreactive (inert)

22. Lanthanides (Rare Earth Metals)
Elements 57-70

23. Actinides Elements 89-102 Transuranic Elements: Synthetic elements

24. Practice!
p. 11 #1, 2
p. 20 #16-20
p. 21 # 4