1. Chemical Periodicty
Patterns of Change

2. Get 2 papers:
One for notes (take notes on all this stuff)
Title one paper “Learning checks” and do this:
Learning check #0
Make your name from different elements
Example
Te B O W
Tellurium = Te
Boron = B
O = Oxygen
W = Tungsten

3. Development of the Periodic Table
Ancient times
Aristotle’s 4 elements
Several pure elements were discovered but the idea of atoms didn’t exist
Elements discovered in ancient times have no English matching symbols

4. Development of the Periodic Table
Mid 1800’s
The idea of atoms was accepted (Dalton)
~ 70 elements known
Early attempts at organizing the elements
- Döbereiner’s Triads
- Newland’s Law of Octaves

5. Döbereiner’s Triads Summarize in your own words:
In 1829 Döbereiner proposed the Law of Triads: The middle element in the triad had atomic weight that was the average of the other two members. The densities of some triads followed a similar pattern. Soon other scientists found chemical relationships extended beyond triads. Fluorine was added to Cl/Br/I group; sulfur, oxygen, selenium and tellurium were grouped into a family; nitrogen, phosphorus, arsenic, antimony, and bismuth were classified as another group.

6. Newland’s Octaves- What does it work for? Why doesn’t it work?
Put into rows of 8 make similar patterns in columns-just like musical notes
What does it work for? Why doesn’t it work?

7. Dmitri Mendeleev Russian chemist
In 1869, published the first Periodic Table of the Elements
Dmitri Mendeleev

8. Mendeleev (cont)
Listed all known elements in order of increasing atomic mass
Arranged the columns that elements with similar properties were side by side…even if out of order by mass.

9. Mendeleev’s Predictions
Left blanks in the table if no element with appropriate properties was known
Accurately predicted properties of missing elements
“Ekaaluminum”
Gallium discovered in 1875
“Ekaboron”
-Scandium discovered in 1877
“Ekasilicon”
-Germanium discovered in 1886
Drawbacks: didn’t account for noble gases and rare earth elements

10. Get 2 papers:
One for notes (take notes on all this stuff)
Title one paper “Learning checks” and do this
Learning Check #1
What information could have really helped Mendelev make the periodic table better?

11. Mendeleev's Periodic table Made the Families

12. Learning Check #2 Matching the families • Alkali metal
• Alkali earth metal
• Rare Earth Metals
• outer transition metals
• Halogens
• Metalloids
•other Non-metals
• Noble gases
• Have properties of metals and non-metals
• This grouping contains Carbon, Oxygen, Sulfur and many others
• a group of reactive non-metals
• in between transition metals and alkali metals
• These rows of elements have very similar properties
• these reactive metals blow up when put in water
• These elements are the “normal” metals, like Gold and Copper
•These elements don’t react with other elements

13. Henry Moseley
Recorded X-ray diffraction data on the elements to determine nuclear charge (write down teacher explanation)
Nuclear charge = number of protons= atomic number

14. Moseley (cont)
Realized that the properties of the elements are related to the number of protons in nucleus
Rearranged the periodic table based on atomic number

15. Man Made elements changed the periodic table
Every element bigger than U
Atoms made by nuclear fusion by adding protons and/ or neutrons
Atoms “smashed” together in a particle accelerator

16. Learning Check #3
What two elements could you combine to make Gold?

17. Glenn Seaborg’s Rearrangement
-based on new, synthetic elements created during the Manhattan project (What was the Manhattan project?)
-he put Th, Pa, and U down below Ce, Pr, and Nd (from the d- block to the f- block)
-this created the actinide series
-it also allowed room for elements 104 to 118

18. Learning Check #4
Write a complete sentence matching the person to the discovery
(Try to use your own memory first, then double check in your notes)
People
• Made the first periodic table
• Found the charge of the nucleus of elements (number of protons)
• Organized the elements into octaves
• Organized the elements into triads
• Moseley
• Mendeleev
• Newlands
• Doberinger

19. Periodic Law
When the elements are arranged in order of increasing atomic number, there is a periodic pattern in their physical and chemical properties
-regular and repeating pattern
metalmetalloidnonmetalunreactive gas

20. Valence Electrons The outermost electrons in an atom
led to chemical properties
The electrons in the highest occupied s and p orbitals
varies from 1-8 for periods 2 & 3
number of valence electrons = group number written with Roman numerals from IA (alkali metals) to VIIIA (noble gases)

21. Learning Check #5: How many valence electrons in each element?Li N O C Ar Mg

22. Modern Periodic Table Periods in horizontal rows
numbered 1-7
Groups in vertical columns
Also numbered 1-18
Also given Roman numerals
S and p block is IA to VIIIA
D block is IIIB to VIIIB (3 times) then IB and IIB
aka; families
s block groups 1-2
p block groups 13-18
d block groups 3-12
f block lanthanides & actinides

23. s-, p-, d-, and f-blocks

24. Learning Check #6
What are two different column names for Gold’s location? What period is Gold in? What block is Gold in?

25. Atomic Size (Radius) Left right in a period size decrease
more protons, therefore electrons are held more tightly

26. Atomic Size (Radius)
As you go down a column, the radius increases in size
Outermost electrons are not held tightly by the nucleus

27. Ionic Radii = the radius of the element when it is an ion
Cations (+) will be smaller than parent atom (lost an electron)
Anions (-) will be larger than parent atom
(gained an electron)
Get’s larger going down

28. Ionization Energy How hard it is to lose an electron/ the energy needed to remove an electron
From left to right, ionization energy increases in a period
Number of core electrons is constant
Number of protons increases
Down a group, ionization energy decreases
Increased shielding as you go down a column
Outermost electrons feel less nuclear charge and are easily removed

29. Electronegativity =how badly it wants electrons
From left to right, electronegativity increases
F has the highest
Down a column, electronegativity decreases
Fr has the least

30. Learning Check #7
For what family is there a difference between electronegativity and ionization energy?

31. Charge
Whether the element gains (negative) or loses (positive) electrons AND how many it usually gains or loses
The pattern is +1 for alkali metals, +2 for alkali earth metals
The charge of transition metals can vary (but always positive) from +1 to +7
Noble gases always have a charge of 0
Halogens = -1
O, S = -2
N, P = -3

32. Learning Check #8
What is a possible charge of Gold?

33. Diatomic Elements This group of elements are never alone
They always form pairs with themselves (unless they are combined with another
Element).
We show that they are in 2’s by putting a 2 for a subscript like H2
The acronym to remember the elements is HOFBrINCl or BrINClHOF (the halogens and some other non-metals)

34. Learning Checks #9 (last one)
What family is calcium in?
Who came up with the periodic table?
How has the periodic table changed over time?
What pattern goes higher down and to the left?
What are all the possible charge of Br?
What is the symbol for elemental oxygen?