1. Ch. 5 PERIODIC TABLE
- Periodic Law
Groups
Periods

3. Mendeleev
1st dude to arrange the elements in order of increasing mass so the similar elements were in the same column (remember this!!!!!)

4. Periodic Law = elements arranged by increasing atomic number
Modern Periodic Law
Periodic Law = elements arranged by increasing atomic number

5. Groups are the vertical columns in the periodic table (1-18)

6. Groups
Elements in Same Group = Act the same!!!!! Just like Mendeleev predicted, NOT BAD FOR AN OLD SCHOOL GUY

7. Groups
Nitrogen (N) will act/behave more like Phosphorus (P) because they are in the same GROUP. Group 15

8. QUESTION
Which element would act most like Fluorine? Sulfur Carbon Chlorine Hydrogen

9. Periods are the horizontal rows of the periodic table (1-7)

10. Sentences are read HORIZONTALLY, and end with a PERIOD.
Periods vs Groups
Sentences are read HORIZONTALLY, and end with a PERIOD.

11. Question
Group Period
Aluminum
Calcium

12. Valence Electrons
Valence Electrons - are the electrons in the OUTERMOST (highest) energy level

13. Octet Rule
Every atom wants 8 valence electrons, so they will gain or lose them to get that 8
8 = Stable

14. Group 18, the noble gases have 8 valence electrons
Octet Rule
Group 18, the noble gases have 8 valence electrons
VERY VERY STABLE, THEY DON’T REACT

15. Octet Rule

16. Phosphorus (neutral) Atomic # = 15 Protons = 15 Electrons = 15
Mass # - Atomic # = # Neutrons
= 16 Neutrons
P = 16
N = 15
Valence Electrons = 5

17. Phosphorous wants 8 electrons in it outer energy level to be stable
Phosphorous wants 8 electrons in it outer energy level to be stable. (8=stable)

18. Gains 3 Electrons to get that magic number 8
Phosphorous ION
Gains 3 Electrons to get that magic number 8
P = 16
N = 15

19. Phosphorous Ion
P-3

20. Magnesium (neutral) Atomic # = 12 Protons = 12 Electrons = 12
Mass # - Atomic # = # Neutrons
= 12 Neutrons
P = 12
N = 12

21. Easier for it to lose 2 electrons to have its lower energy level full
Magnesium Ion
Easier for it to lose 2 electrons to
have its lower energy level full
P = 12
N = 12

22. Magnesium Ion
Mg +2

23. Charges of the groups
Group 1 = +1
Group 2 = +2
Group 13 = +3
Group 14 = +/- 4
Group 15 = -3
Group 16 = -2
Group 17 = -1
Group 18 = 0 (stable)

24. Color ANOTHER periodic table
Read through pages and color the 8 different categories of elements from the book on your small periodic table

25. Electro negativity
Electronegativity – ability of an element to attract electrons (-) to itself

26. Electro Negativity
Trend in periodic table: Increases from LEFT – RIGHT Increases from BOTTOM - TOP

27. INCREASING ELECTRONEGATIVITY

28. Which element has a greater electronegative value?Be Na O Ca

29. TAKS TOPIC REMEMBER THIS
FLUORINE – most electronegative element (best looking element, everything is attracted to FLUROINE)

30. Atomic Radius – how big an atom is in size

31. Atomic Radius
Atomic Radius trend: -INCREASES from RIGHT – LEFT - INCREASES from TOP - BOTTOM

32. INCREASING ATOMIC RADIUS

33. Question
Which element has the biggest atomic radii? Sr B F Be