Monday, February 14

We started today's chemistry class off with a little valentines day fun. Mr. H brought in a small packet, and when he hit it, a foil balloon shaped like a heart expanded inside. He explained that this was caused by the reaction of two substances, and the gas was the product. When he hit it, it reacted the two substances.

But now on to what we learned in class today. We flipped our packets to page 5 and read the first two paragraphs. This explains how electrons are configures within the orbitals of atoms. There are 2 atoms per orbital, and all orbitals in a sublevel must have one electron in them before one can have two.

We then tried some examples on the next page, I'll give you a few answers.

H 1 electron 1s1
He 2 electrons 1s2
C 6 electrons 1s2 2s2 sp1

Above this table is a diagram that shows the order of all the orbitals.

Next Mr. H taught us a shortcut. For elements that are large, and would take a long time to write out their entire electron configurations, you just put the symbol for the closest noble gas that is before the element, and then the electron configurations up to that element.
Example. For Barium.
[Xe] 6s2

Then Mr. H told us how electron configurations explain the orientation of the periodic table. I have a picture here that helps explain it.

The location of the atom determines what the last energy level will be, based on this diagram. Also, this is useful for using the shortcut.

At the beginning of class Mr. H told us we would use the computers, but we never did. I guess it took a long time to learn this. I hope we get to use the computer tomorrow!