1. The Periodic Table

2. Metals Nonmetals Semimetals

3. Metals Nonmetals Semimetals
Metals- hard, shiny, conductors, react with acids
Non metals- typically gases, brittle if solid, bad conductors, rarely react with acids

4. Metals Nonmetals Semimetals
Semi-metals- have both metal and non metal properties, sometimes look like they contradict each other. Ex: Silicon- brittle but shiny and conducts electricity

5. History of its Development
Johann Dobereiner-1817, German

6. History of its Development
Johann Dobereiner-1817, German
Discovered that Ca,Ba,Sr had similar properties so he grouped them into a “Triad” in order of mass

7. Dobereiner Triad 1 Ca:Sr:Ba Triad 2 Cl:Br:I Triad 3 S:Se:Te
*He noticed that the middle element’s mass was very close to the avg. of all 3.

8. John Newlands,
62 known elements

9. John Newlands, 1863-65 62 known elements
Arranged them in order of increasing atomic mass and noticed a repetition of properties every 8th element.

10. John Newlands,
His P.T. is grouped into a period of 7 elements stacked into rows.
He called it the Law of Octaves

11. John Newlands,
Li Be B C N O F
Na Mg Al Si P S Cl

12. Dmitri Mendeleev, 1869
Russian Teacher

13. Dmitri Mendeleev, 1869
Russian Teacher
Suggested that properties of elements were dependent upon atomic mass (wrong).

14. Dmitri Mendeleev, 1869
Also noticed that some elements appear to be in wrong row because they did not have similar properties: Te & I, Co & Ni, Ar & K.

15. Dmitri Mendeleev, 1869
He arranged some elements out of their atomic mass order so the properties would align vertically.

16. Dmitri Mendeleev, 1869
He left gaps in his table when properties didn’t align, predicting that a yet to be discovered element belonged there. Ex: Ge, discovered in 1886.

17. Henry Moseley 1913
Explored the nucleus with X-rays.,

18. Henry Moseley 1913 Explored the nucleus with X-rays.,
Discovered that the “atomic number” is equal to the number of protons.

19. Henry Moseley 1913
He ordered the elements by atomic number (not mass or properties) and found that the properties still matched up vertically.
This was the Modern P.T.
Periodic Law: properties of elements are determined by their atomic number.

20. Families of the Periodic Table
Family= group, vertical row
Group 1A Alkali Metals
Li Na K Rb Cs Fr

21. Families of the Periodic Table
Alkali Metals Properties-shiny, malleable, very reactive to water, Reactivity increases down the group

22. Families of the Periodic Table
Alkaline Earth Metals- Be Mg Ca Sr Ba Ra are shiny, malleable, moderately reactive, slight radioactivity in Ra and Ba

23. Families of the Periodic Table
Boron Family-B to Tl, have both metallic and nonmetallic properties
Carbon Family- C to Pb, metals and nonmetals, Pb & Sn can be toxic

24. Families of the Periodic Table
Nitrogen Family-N to Bi; nonmetals and metals As, Sb, Bi poisionous
Chalcogens- O to Po, all nonmetals e/c Po, Te

25. Families of the Periodic Table
Halogens- F to At, gas, liquid and solid , most reactive nonmetals
Transition Metals- Groups 3 to 12 elements, very versatile

27. Families of the Periodic Table
Lanthanides & Actinides elements 57 to 70; 89 to contain synthetic elements, most are radioactive

28. Families of the Periodic Table
This family goes through transmutation more readily than other families

29. Families of the Periodic Table
Transmutation- the process of spontaneously changing into another element

30. Families of the Periodic Table
Alpha Decay
Beta Decay
Positron Emission
Electron Capture
Gamma Emmision

31. Trends in the Periodic Table
Called “Periodicity”
Atomic Radius- increases down the PT and increases as you go left.
Biggest Atom?
Smallest Atom?

32. Trends in the Periodic Table
Ionization Energy-energy needed to remove a valence electron
Increases as you go up and right---opposite of atomic size

33. Trends in the Periodic Table
Electron Affinity- ability to attract an electron from another atom
Increases as you go up and right-same as I.E.

34. Trends in the Periodic Table
Electronegativity- rating scale indicating an element’s ability to attract electrons
Trend: same as I.E.

35. Trends in the Periodic Table