Wednesday, April 28, 2010

Beginning Gasses

Today we started learning about the behavior of gases and the factors that affect them. Gases are lightweight fast moving particles that generally have a lot of empty space between them. Because of this, they are easily compressible (pictured left). If not contained, gases can spread (or diffuse) to fill any size and shape container.

Gases are affected by pressure, volume, number of moles, and temperature. Changing any one of these variables, changes all the others.

Today we also learned the formula for the Law of Partial Pressure. Basically partial pressures add up to form total pressure. If the total pressure is given then you subtract the partial pressures.

We are still working on moles and making sure we have stoichiometry down pat.

Thursday, April 22, 2010

Bubble gum!

Students each had a piece of gum - one they brought in or one from me. They all brought in chewing gum (even though the board said bubble gum) and I brought in bubblegum, so there was some trading. Students observed the gum by weighing it, drawing it, and smelling it.

Next they chewed the gum for ten minutes. While they were waiting we watched How Its Made on bubblegum. We also had a little fun blowing bubbles.

After ten minutes, students did more observations and re-weighed the gum. The gum weighed less... why? Because the sugar dissolved and was lost. Using this weight difference, students determined the percent composition of sugar in the gum they chewed. We worked on making a data chart to make some comparisons and we will finish this on Friday.

Wednesday, April 14, 2010

Measuring moles

Today students measure how many moles and molecules of water they could drink. They took some measurements and then did some mole calculations to figure everything out. The determined how many moles and molecules they could use when writing a message with a piece of chalk, and measured sugar by biting into a candy corn pumpkin. There are some interesting statements written on the board.

Everyone should take this one to heart, "If there is faith that can move a mountain, it's faith in your own power." I know that the students can do these calculations and most of my time these days is walking around confirming the student is right and pep-talking. They can do it... they just need to believe that they can.

Monday, April 12, 2010


Today students took a mole challenge to see how much they knew about moles... besides their favorite number. The high score was a 9.5/10 so I must have stumped them. They did do better than they thought they would... and most of them were a bit mad when they saw what the answers were to the ones they didn't know.

For moles there are basically three conversions to know.
1 mole
6.02 x 10^23

1 mole
(molar mass) grams (add weights from PT)

1 mole
22.4 Liters

Today we learned about Avogadro's theory about gases and then practiced converting using our new favorite number, 22.4. Avogadro, that handsome devil, did a lot of important stuff with moles and is also the guy who gave us our other favorite number 6.02.

Everyone seemed to have the hang of things so we got out the white boards and did some practice problems. Everyone tried the problems and erased any mistakes with ease. I know they know it even if they feel a little overwhelmed.

Monday, April 5, 2010

Winners for Element for President

Congratulations to everyone who participated in this year's election! Special congratulations go out to the top six winners...

1. Silicon - Austin!
2. Gold +1 - Ashley
3. Lead
4. Americium
5. Radon - Rick!
6. Argon - Olivia!

Numbers 1, 5 and 6 come from my classes. The others are in Mrs. Woodward's chemistry classes.