1. Between you and a partner, grab one textbook…
Turn to p. 193 (Organize Elements minilab)
Cut a piece of construction paper into 10 squares and write the information for each element on each separate sheet
Follow the instructions and answer the questions on a separate sheet (one sheet per pair)

2. For quiz b 3 2

3. Chapter 6
Periodic Table

4. Development of the Periodic Table
J.W. Dobereiner
Early 1800’s, classify elements in sets of 3
This trend didn’t work for most of the elements known at the time
Element
Mass Li 7 Na 23 K 39

5. John Newlands
1865 – noticed trend that every 8th element had same properties (law of octaves)
Unfortunately, this didn’t work for all the known elements at the time, and it was dismissed

6. Mendeleev Considered the father of the modern Periodic table
arranged by increasing
atomic mass (1869)

7. Moseley Discovered that the # of protons = atomic number
Developed concept of arranging PT by atomic number
Periodic law – there is a periodic repetition of properties when elements are arranged by atomic #

8. Parts of the Periodic Table
Periods vs. groups/families
Metals vs. nonmetals vs. metalloids
What are some properties?
Are all nonmetals gases?
Representative elements vs. transition metals vs. inner transition metals

9. Electrons What do all elements in the same group have in common?
Valence electrons
All elements in the same group exhibit similar characteristics
Sodium and Potassium are both highly reactive in water
So, what subatomic particle is responsible for determining properties of an element?
Electrons

10. How many valence electrons?
Alkali metals:
1 valence electron, s block
Alkaline earth metals:
2 valence electrons, s block
Halogens:
7 valence electrons, s and p block
Noble gases:
8 valence, totally filled s and p block, except for which element?
Helium – his s block is filled with only 2
Have students write the electron configuration for a few elements in different families

11. Transition metals: (Groups 3B – 12B)
2 s-block electrons, and various d block electrons
Called transition metals b/c electrons can move around the d block
Inner transition metals:
2 s-block electrons and various f block electrons
Representative elements: (Groups 1A – 8A)
any of the s or p-block elements
Have students write the electron configuration for a few elements in different families

12. SHIELDING Shielding Which atom has more shielding?
We’ll be coming back to this idea of shielding often

13. Atomic Radius Half the distance between the nuclei of 2 like atoms
No definite edge of electron cloud
atomic
radius

14. Trends in Atomic RadiusBe C F
Down the Groups
What is changing about the atom as we go down?
# of shells = energy level
More shells = bigger atom
Across the Periods
Same period means same # of shells
What is changing as we go across a period? Li Na K Rb

15. Put the following elements in order of increasing atomic radius
Who is larger?
Mg or S?
Br or K?
C or Sn?
Who is smaller?
Li or N?
F or I?
Put the following elements in order of increasing atomic radius
Ca, Fe, Br, O, Ba

16. What is an ion? An ion is an atom with a charge (+ or -)
In a sodium atom, how many protons and electrons do we have? How many valence e-?
11 p+ and 11 e-
1 valence e-
Can we lose protons?
No, that would change the element

17. Octet rule An atom is most stable when it has a full outer shell
How many valence electrons = full?
An atom will lose or gain electrons to achieve this – whichever is easiest
Sodium has 1 valence electron. Do you think he loses or gains?
Loses, then there will be 1 more proton than electrons

18. If an atom has 2 valence e-, what will it do?
What group is this? What charge?
What charge does aluminum form? Lose or gain?
+3, loses 3 electrons
If an ion is positive it has ______ e-
If an ion is negative it has ______ e-

19. Size of Ions (Ionic Radius)Na
Na+ e- F- F e-

20. Who is larger? Mg or Mg2+? S or S2-? O2- or F1-?
First, determine if you have lost or gained electrons… Which particle do you have more of (who has the power?)

21. Ionization energy
IE is the energy required to remove an electron from an atom (and make it an ION)
KEEP SHIELDING IN MIND
Babysitter analogy
A couple First Ionization Energies:
Li = 520 kJ/mol
O = 1310 kJ/mol
Who is harder to take an electron from?

22. Which has the higher ionization energy?
Li or N?
Cs or Li?
O or S?
Which has the lower ionization energy?
K or Fe?
F or Br?

23. Turn in projects up front…
Warm up:
As we go down the groups on the PT, the size of the atom __________, making it __________ to take an electron away, making the ionization energy __________
As we go left to right across a period, the size of the atom _________, making the ionization energy __________.

24. Arrange in decreasing ionization energies:
Cr, Br, I, Li, N

25. Electronegativity (EN)
How well an element can attract electrons from another element in a bond
Atoms fill their outer shells when they bond with another atom
How might EN relate to IE?
If it’s hard to take an electron away, what kind of attraction do you think it has?
What do you think the electronegativity of a noble gas might be? Do they want to bond?
Zero

26. Arrange in order of increasing electronegativity:
Mg, F, Ne, Cs, Al

27. NOW THE EASY WAY… IE and EN increase RaDius Decreases
& OVER
IE and EN increase
RaDius Decreases UP
But it is good to understand the WHY so you can double check yourself…

28. Put in order of decreasing atomic radius:
Ca, Al, Ne, Rb, Br, Au, Zn, C
What order is this for ionization energy? (increasing or decreasing)

29. Skip #8
Add this question (doesn’t matter where):
Determine the larger radius in the following:
a. Mg or Mg2+ (what are the the
b. Cl or Cl1- things with charges
c. Cl1- or P3- called, and how do
they get those charges?)

30. Continue from yesterday…
Between you and a partner, grab a textbook:
Turn to p. 193 (Organize Elements minilab)
Cut a piece of construction paper into 10 squares and write the information for each element on each separate sheet
Follow the instructions and answer the questions on a separate sheet (one sheet per pair)
When finished, turn it in and grab a BINGO card