1. Do Now What is the most likely atomic radius of element Yy? 103 pm

2. Do Now
Write down three questions you still have about periodic trends

3. Periodicity, Part 3
Williamsburg high school for architecture and design
Mr. Quinn and Ms. Tom
10/30/13

4. Aim
How can we explain trends in atomic radius and electronegativity across periods?

5. Think Back: What happens to atomic radius across a period?
What happens to electronegativity across a period?

6. Two Factors of Gravitational Pull
Size of the objects
Distance of the objects

7. Gravity: the Earth and the Moon
Gravity is independent of number of objects!

8. Gravity and Size…
Gravity is dependent on the size of objects!

9. Gravity vs. Electrical Force
???

10. So What About Nuclear Charge?
Nuclear charge increases left to right!

11. One Difference between gravity and electrical pull:
Electrical pull can be lessened by opposite charges.

12. Two Quick Definitions Valence Electrons: electrons in the outer shell
Kernel Electrons: electrons not in the outer shell

13. Fade Into Obscurity…

14. Round 2 …

15. Recap:
Number of valence electrons doesn’t affect the pull on EACH electron
A larger nucleus pulls harder
Having electron shells in the way obscures the nucleus

16. Spy vs. Spy, Round 1
The distance across an atom of an element in the solid phase is pm. The atomic radius of an atom of this element is closest to
64 pm
128 pm
256 pm
512 pm

17. Spy vs. Spy, Round 2
Which of the following electron configurations represents the element with the smallest atomic radius?
2-4
2-5
2-6
2-7

18. Spy vs. Spy, Round 3 The ability of carbon to attract electrons is
greater than that of nitrogen, but less than that of oxygen
less than that of nitrogen, but greater than that of oxygen
greater than that of nitrogen and oxygen
less than that of nitrogen and oxygen

19. Spy vs. Spy, Round 4
Atoms of which of the following elements have the smallest atomic radius? Si P S Cl

20. Spy vs. Spy, Round 5
Which Group 17 element has the least attraction for electrons? F Cl Br I

21. Spy vs. Spy, Round 6
An atom of which element has the greatest attraction for the electrons in a bond with a hydrogen atom?
Chlorine
Phosphorus
Silicon
Sulfur

22. Spy vs. Spy, Round 7
As the elements is Period 3 are considered in order of increasing atomic number, there is a general decrease in
atomic mass
atomic radius
electronegativity
first ionization energy

23. Spy vs. Spy, Round 8
Which electron configuration represents the atom with the largest atomic radius? 1
2-1
2-2
2-3