Friday, Febraury 19, 2011

Today, class started off by reviewing what we did in class the day before and the blog post put together by Katie. Then, we received the answers to a previously due Web Assign in our packet on page 17 which was a 6.8 reading sheet. The answers are:
1. b
2. d
3. They represent the number of s, s+p, s+p+d electrons....etc.
4. b
5. b,c
6. a,b,c
7. d
8. a
9. d
10. a
11. d
12. b
13. b
14. a, d
15. b
16. d
17. F, Rb

Also, Mr. H showed the class where the highest number of people viewing the blog came from which included interesting places such as Germany, but of course it was mainly from the United States. I would like to say Hi to all the people that are reading this blog not in our class.

After, we moved on to page 10 in the packet which had explainations for the periodic trends of atomic radii, Ionization energy and Electronegativity.

The following is what Mr. H explained in the class as the reason why when moving from left to right on the periodic table the size of the atomic radii decreases: Additional protons led to an increase in nuclear charge=the outer orbitals are pulled inward and shrink.

Explaination for when moving from top to bottom the atomic radii increases: The outer most electrons are entering orbitals that are larger thus the size of the atom increases.

Explaination for why when moving from left to right across the periodic table the Ionization Energy increases: The nuclear charge increases and pulls with more force on the outer electron thus it takes more energy to remove outer electrons.

Explaination for why when moving from top to bottom on the periodic table the Ionization energy decreases: The outer most electrons are entering orbitals that are larger; thus being further away the electrons are pulled away with less force and requires less energy to remove them.

Mr. H said that the explainations for Electronegativity weren't needed, so we skiped that part. The rules though are moving from left to right the electronegatvity increases and going from top to bottom the electronegativity decreases.

Katie's blog has diagrams and graphs that show the properties of all three trends on her blog.

Once we finished learning about the explainations we went to the computer lab to work on upcoming Webassigns or labs that were due.

Homework for the weekend is to study for the test and finish the Webassigns one of which is optional or you could to both to earn yourself an extra throwout at the end of the quarter.