1. Periodic Trends

2. ATOMIC RADIUS

3. What is It?

4. HOW TO MEASURE ATOMIC RADIUS?
Ideally –
measure from nucleus to edge of last filled orbital (valence orbital)

5. HOW TO MEASURE ATOMIC RADIUS?
CAN’T!!! --- Orbitals are just estimations of where electrons might be. The edge is “fuzzy.”
So measure ½ the distance btwn two identical atoms bonded together

6. What is the pattern?

7. HOW DOES ATOMIC RADIUS INCREASE
HOW DOES ATOMIC RADIUS INCREASE? LeftRight or RightLeft, Top Bottom or Bottom Top?
Element
Atomic #
Atomic Radius H 1
0.37 Li 3
1.23 K 19
2.03 Na 11
1.57 P 15
1.10 Cl 17
0.99

8. HOW DOES ATOMIC RADIUS INCREASE?
INCREASES from RIGHT  LEFT TOP  BOTTOM

9. Why????

10. SO WHY DOESN’T YOUR RADIUS GET BIGGER????
INCREASES DOWN a GROUP Adding more energy levels
DECREASES L  R ACROSS A PERIOD
but - ADDING more protons, neutrons, electrons.
SO WHY DOESN’T YOUR RADIUS GET BIGGER????
More protons = the more they can PULL IN e = SMALLER radius
GREATER EFFECTIVE SMALLER NUCLEAR CHARGE RADIUS =

11. RANK FROM SMALLEST RADIUS TO BIGGEST
Jumpstart #1-D
Fluorine
Helium
Cesium
Francium
Vanadium
Zinc
Silicon
Yttrium
Phosphorus
4 minutes

12. IONIZATION ENERGY

13. What is It?

14. IONIZATION ENERGY
Official Definition of Ionization Energy: The energy required to remove one electron from a neutral atom of an element What that REALLY means: How hard it is to remove an electron from the atom (more energy needed, the harder it is)

15. What is the pattern?

16. HOW DOES IONIZATION EN. INCREASE? LR, RL, Top Bottom, Bottom Top?
Element
Atomic #
Ionization Energy H 1
13.6 Li 3
5.4 K 19
4.3 Na 11
5.1 P 15
11.0 Cl 17
13.0

17. IONIZATION ENERGY
INCREASES from LEFT  RIGHT, BOTTOM  TOP

18. Why????

19. Why does IONIZATION ENERGY increase the way it does?
INCREASES LEFT to RIGHT
atoms want a full valence shell…they DONT want to give away their electrons IF they are almost full!
INCREASES BOTTOM to TOP electrons are CLOSER nucleus so they are being held onto tightly

20. ELECTRONEGATIVITY

21. What is It?

22. ELECTRONEGATIVTY
Official Definition of Electronegativity: A measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound What that REALLY means: How strongly it can pull on electrons from another atom

23. What is the pattern?

24. How Does Electronegativity Increase?
High Ionization Energy 
_______ to take electrons away 
They really ________ electrons 
Pulling ______ on another atom’s e-
 Because of _____ electronegativity
Want Don’t want
Hard Easy
High low

25. ELECTRONEGATIVITY
INCREASES from LEFT  RIGHT BOTTOM  TOP

26. Why???

27. WHY?????? INCREASES LEFT to RIGHT
Atoms are closer to filling valence shell, so they REALLY want more electrons
INCREASES BOTTOM to TOP Electrons are CLOSER to nucleus – can pull harder on electrons

28. Reactivity

29. What is It?

30. Elements in the same group have similar behaviors
Because they have the same number of valence electrons!!!
BUT MAGNITUDE CHANGES!

31. What is the pattern?

32. Why???

33. Reactivity in Groups
Metals – more reactive as you go DOWN
Easier to lose electrons
because valence electrons are further away from nucleus
Lower ionization energy
Non-metals – more reactive as you go UP
Smaller the atom the more it wants an electron to gain
Higher electronegativity means its easier to take one from another atom
Brainiac Video
Disposal of Sodium

34. Reactivity Already have a full shell! Don’t want to lose it!
Least Reactive - INERT
Most Reactive
Already have a full shell! Don’t want to lose it!
Closest to a full Octet – Full Valence Shell
Most Reactive

35. RANK FROM SMALLEST IONIZATION ENERGY TO BIGGEST
Fluorine
Helium
Cesium
Francium
Vanadium
Zinc
Silicon
Yttrium
Phosphorus
Jumpstart #2-D
Get out green pens
Get out colored pens/pencils/markers
Get out gluesticks

36. FOLD PERIODIC TABLE IN HALF AND GLUE TO PAGE 84
P. 83 – I can apply periodic trends to ranking sets of elements
P. 85 – I can see many patterns and find lots of information on the periodic table
FOLD PERIODIC TABLE IN HALF AND GLUE TO PAGE 84

37. Help set up a lab for Monday!
1ST PERIOD – BLACK LAB TRAYS and FOUR PAIRS OF GOGGLES PER LAB BENCH
3RD PERIOD – FORCEPTS and TWO WEIGH BOATS
4TH PERIOD – WATER SQUIRT BOTTLES – MAKE SURE THEY ARE FILLED WITH DISTILLED WATER
5TH PERIOD – FOUR SMALL BEAKERS
6TH PERIOD – PHENOLPHTHALEIN INDICATOR