uiop

1. Modern Periodic Table
Mrs. Coyle

2. Part I
 Introduction.
 Periods and groups.
 Metals, nonmetals and metalloids.

3. The Modern Periodic Table
 The Periodic Table is a listing of all the
known elements.
 The elements are organized by:
 Atomic number
 Chemical Properties
 Interactives . The Periodic Table . Groups
(learner.org)

4. Groups and Periods
 Group( or Family): a vertical column.
Elements in groups have similar
chemical properties.
 Period: a horizontal row.

5. Groups and Periods are
numbered.
 There are 7 periods.
 There are 18 numbered columns.

7. IUPAC
 International Union of Pure and Applied
Chemistry
 1985 new system for labeling groups.

8. Metals, Nonmetals and Metalloids
 Elements can be classified into:
 Metals
 Nonmetals
 Metalloids (semimetals)

9. Metals
Metalloids
Nonmetals

11. Actinides and Lanthanides

12. Physical Properties of Metals
 Good conductors of electricity and heat.
 Malleable (can be hammered into sheets).
 Ductile (can be drawn into wires).
 Lustrous.

13. Chemical Properties of Metals
 Easily lose electrons.
 Form positive (+) ions.

14. Nonmetal Physical Properties
 They do not have the properties of
metals.

15. Nonmetal Chemical Properties
 Gain electrons.
 Form negative ions.

16. Part II
 Valence Electrons
 Group 1
 Group 2

17. -Niels Bohr’s Model –
Distinct Energy Levels

18. Periods
 The periods (rows) of the periodic table
indicate the highest energy level
occupied by one or more electrons.

19. Valence Electrons
 The electrons the occupy the highest
energy level of an atom.
 Valence electrons play a key role in the
chemical properties of an element.

20. “A” Groups (Old System)
 The “A” groups are numbered 18.
 The number of the “A” groups
correspond to the number of valence
electrons.

21. Group 1- Alkali Metals
 1 valence electron (ns1)
 Form a 1+ ion.
 Note: Hydrogen, a nonmetal, is located
in the first column because it has one
valence electron.

22. Group 1- Alkali Metals
Lithium
Sodium
Potassium
Rubidium
Cesium
Francium

23. Sodium’s Reaction with H2O
Produces Hydrogen

24. Reactivity of Alkali Metals
 Increases from top to bottom of the
group.
 Which is more reactive Cesium or
Sodium?

25. Note:
 Sodium and Potassium are stored in oil
to keep them from reacting with oxygen
and water in the air.
 Cesium is stored in glass tubes of argon
gas( an inert gas).

26. Group 2- Alkali Earth Metals
Beryllium
Magnesium
Calcium
Strontium
Barium
Radium

27. Group 2- Alkali Earth Metals
 Have 2 valence electrons.
 Form 2+ ions.

28. Group 2- Alkali Earth Metals
Reactions with Water
 Be does not react with water.
 Mg reacts with hot water.
 Ca, Sr, Ba react easily with cold water.
 Which way along the group does
reactivity increase?

29. Notes:
 There is Mg in chrolophyll
C55H72O5N4Mg
 Calcium is in your bones,
chalk, limestone,
toothpaste, pearl (all as
calcium carbonate).

30. The Periodic Table