2. “Meet the Elements” by They Might Be Giants What is an element vs. a compound?

3. Some elements can be found “native” in nature. People have known about these for a long time!

4. Then people wanted to turn worthless base metals into gold…

5. “More than 300 years ago, in 1669, Hennig Brand, a Hamburg alchemist, like most chemists of his day, was trying to make gold. He let urine stand for days in a tub until it putrified. Then he boiled it down to a paste, heated this paste to a high temperature, and drew the vapours into water where they could condense - to gold. To his surprise and disappointment, however, he obtained instead a white, waxy substance that glowed in the dark. Brand had discovered phosphorus, the first element isolated other than the metals and non-metals, such as gold, lead and sulphur, that were known to the ancient civilisations.”

6. Periodic Table of Elements may SEEM boring…But people LOVE to organize things:

11. In 1869, Mendeleev organized the elements by their properties. He noticed a repeating pattern in the ~60 elements known at the time when he organized them by atomic mass! Father of the Periodic Table Dmitri Mendeleev (1834-1907)

12. Video – Alkali Metals

13. Gallium Germanium

14. Two Years Later…

15. Father of the Modern Periodic Table: Henry Moseley (1887-1915) in 1913, through his work with x-rays, Moseley discovers the actual nuclear charge of the elements, which we now call atomic numbers. Moseley then rearranges the periodic table by increasing atomic number. This is the periodic table we use today- the modern periodic table.

16. Father of the Modern Periodic Table: Henry Moseley (1887-1915) *“There is in the atom a fundamental quantity which increases by regular steps as we pass from each element to the next. This quantity can only be the charge on the central positive nucleus.” -Henry Moseley

18. Label your periodic table: \ Which has similar properties?

19. \ Why do elements in the same group have similar chemical properties?

20. Label these sections: Ductile, malleable, good conductors Brittle, poor conductors

21. Group 1: Alkali Metals Soft – cut with a knife! Highly reactive! - 1 valence electron –Explodes in water! –“Rusts” almost instantly –Never found in elemental form in nature You have to store them coated in mineral oil or argon to keep them from reacting!

22. Group 2: Alkaline Earth Metals Still reactive, but not as reactive as the alkali metals. 2 valence electrons

23. Group 3-12: The Transition Metals Generally stable and malleable metals. Contains the only magnetic elements –Fe, Co, Ni Contains gold, silver, and platinum Have various numbers of valence electrons

24. Group 17: The Halogens Highly reactive non-metals 7 valence electrons Form diatomic molecules (like Cl 2 ) that are more stable than elemental form Fluorine is so reactive that it will attack glass and can even force the noble gases to form compounds with it –Fluorine is a jerk…but is not the same as fluoride!

25. Group 18: The Noble Gases Noble gases – gaseous elements with EXTREMELY low reactivities (they are inert) 8 valence electrons