1. A.E.Beguyer de Chancourtois
Henning Brand
Johann Dobereiner
jean baptiste dumas
Brand- discovered phosphorus. Johann-atomic weights
 Leopold Gmelin
Max von Pettenkofer
A.E.Beguyer de Chancourtois

2. Dmitri Mendeleev
A Russian chemist, considered to be the “Father of the Periodic Table”
Grouped up discovered elements based on measureable properties:
Density, appearance, and melting point
Scientists have taken all of the elements and tried to group them together based on their properties.

3. The “Periodic” Table
Mendeleev saw that when the elements were arranged in order of increasing atomic mass, those that had similar properties occurred in a repeating pattern.
This pattern was periodic
He found that this pattern repeated every 7 elements

4. Dashes represent missing elements, gaps in the pattern
Dashes represent missing elements, gaps in the pattern. He left them open and decided that they just havnt been discovered yet

6. The Periodic Table Elements are organized by their properties
Horizontally (Row or Period) – increasing atomic number (number of protons and electrons)
Your senses tell you things. When you touched the liquid, you expected it to get wet. When you smelt the beaker, you expected to get a smell.
The location of an element on the periodic table is just like your senses: it tells you things.

7. The Periodic Table
Vertically (group or family) – elements with similar chemical properties
Family Number is the number of valence electrons
Your senses tell you things. When you touched the liquid, you expected it to get wet. When you smelt the beaker, you expected to get a smell.
The location of an element on the periodic table is just like your senses: it tells you things.

8. Transition Metals Groups/Families Alkali Metals Alkaline Earth Metals
Boron Group
Carbon Group
Nitrogen Group
Oxygen Group
Halogen Group
Noble Gases
Alkali Metals react explosively with water, have similar bonds cowar
Transition Metals

10. Metals All solid except Hg (mercury)
Shiny, good conductors of electricity and heat
Ductile (can be made into a wire)
Malleable (can be pounded into sheets)
Mercury – only liquid metal at room temperature. Thermostats, found in fatty fish that lived in water that was contaminated by coal burning plants
Iron – horseshoes, ancient tools, modern-day tools,
Zirconium – from mineral zircon. Used as jewelry…. Diamond like

11. Nonmetals Opposite of metal properties Brittle Not malleable
Not ductile
Poor conductors
Chlorine – pale yellow gas that was used as mustard gas during WW1 to kill soldiers, today used for cleaners, pool, bleach, etc
Phosphorus – white colored, most dangerous, used for matches
Sulfur – one of few NATURAL occurring elements. Sulfur componds is responsible for giving onions and garlic their smell

12. Metalloids 7 of them Properties are a mix of metals and nonmetals
Economically important due to unique properties
Boron – extremely hard in pure form, but extremely brittle. Boric acid is Found in Silly Putty, gives it its elastic texture
Arsenic – poisonous, semiconductor with gallium to produce high speed circuits for supercomputers and cell phones
Silicon – Found in, TV, sand, silicone gels. Projectors, watches, etc.

13. 92 natural elements, the rest are synthetic
The world is made up of matter, which make up elements. Examples:

14. Atoms Atoms are the basic building blocks of matter
Ask students to draw what they think an atom looks like on their notes

15. Electrons – negative (-)
Protons – positive (+)
Neutrons – neutral (0)
Electrons – negative (-)
Review periodic table

16. Atomic Number - # of protons and electrons
Symbol – Symbol of element
Name – Name of element
Atomic Mass – average weight (protons and neutrons)

18. Mass Number - (minus) Atomic Number = # of Neutrons
= # of Protons
= # of Electrons
Mass Number - (minus) Atomic Number = # of Neutrons