1.27.11

Announcement: None

Homework: None

Today we started with taping in about 30 or more sheets on the new unit. After that we took the quiz on the mole equations. Once everyone was done, Mr. Paek introduced the unit of stoichamerty, but we didn't really get through much. We learned that it's basically like the mole equations, but instead of moles you would switch it for atoms.

Example worksheet:

You can refer back to the previous post to better understand whats on the worksheet.

Next Sciber-Brandon

1.26.11

Announcements: Study for tomorrows mole quiz and the other upcoming quizzes.

Homework: Journal pages 7-8

Today we started with a new mole lab, testing the mass of different elements, how many moles are in the molecule and how many molecules are in the mole. For each of these ways you have to use conversion factors.

For example finding how many moles in krypton.

2.7 x 10^14 x 1mol/6.02 x 10^23

=4.49 x 10^-14

Also finding how many atoms are in an mol.

Ex. Aluminum atoms

89.35 x 6.02 x 10^23/1mol

= 5.38 x 10^15

Next Scriber- Peter

1.24.11

Anouncements: We will be starting to take a variety of quizzes starting this Thursday on the Mole unit. This unit is crucial so if you do not understand go see Mr. Paek or the TLC!!

Homework: Finish the Pair, Dozen, Mole Lab!! (3 pages)

Today in class we started the new Mole unit and learned the concept of a mole in order to solve mole problems. We learned that 1 mole= 6.02 x 10E23 (10 to the 23rd power).

In order to fully understand the concept of a mole, we did a Mole Lab and started by reviewing the fact that a pair is always 2 and a dozen is always 12. Like those, a mole is always 6.02 x 10E23.

During the lab, we practices converting problems involving the atoms mass in grams. Each elements atomic mass on the periodic table is the amount of mass measured in grams per mole. For example, Al has an atomic mass of 26.98.

26.98g of Al = 1 mole of Al

Another way of saying this is that for every 26.98g of Al, there is one mole of Al.

We also were able to add up the masses of two different atoms such as (H2O) two Hydrogen and one Oxygen so that we were able to figure out that there are 18.02g in a single H2O molecule. Like the concept Al's mass of 26.98g being a mole, 18.02g of H2O is equal to 1 mole as well.

Next Scriber: Dan

1.25.2011

Homework: journal pages 1-6





Today we started class by going over the lab from yesterday. We also went over the fact that to convert grams to moles ( or vice versa), you have to convert it to moles first. For example, if you wanted to find the number of molecules in 0.0908 grams of NiCl2 you need to go through at least to steps to solve. First you need to cancel out grams:


1 mole


0.0908 g x ---------


129.59 g





Then, you need to cancel out moles to find your final answer:


1 mole 6.02 x 10^23


0.0908 g x --------- x ------------


129.59 g 1 mole





This equals 4.22 x 10^20 molecules of NiCl2








Next Scriber: Cyril