What's Inside the Box?

Due to the many absentees from class today, we have a special guest blogger...none other than the undisputed champion of GBS honors chemistry...Mr. L!
The first part of class was spent discussing the test that was taken on Thursday (9/23). If you were not here, please feel free to come in and see you test. Just let me know what time would be best for you.
The rest of class was spent as an introduction to the next unit. See the moodle site for the unit objectives and calendar.
Mr. Lieberman first showed us his "think tube"...amazing, but how does it work.

the answers

That does not look like a black box!

We then worked on the black box activity. The students were asked to figure out the "maze" that was inside the "obstertainer" by using the marble that was inside. The only rule was that we could not open the "boxes". The students used many different techniques to visualize what was inside the "boxes", but still came out frustrated because they wanted to know the right answers. After about 5 minutes of playing, we came back to the front of the room and discussed how this relates to the model of the atom. The point was made that, we believe that atoms exist and so do the parts inside (protons, neutrons, electrons) but we can not observe them directly. Lab data and experimentation has to be used in order to draw conclusions about what cannot be seen. From this we can start to build models of matter. So what is the process of discovering the insides of atoms. The evolution of the atom starts with the ancient Greeks as they were the first to use the idea of the atom.The idea of the atom was first used by the philosopher Democritus It was noted that the greek model of matter was not very good because now data was used to support it.

Atomic history day #1

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This is as far as we got and the discussion will continue on Monday. Please make sure that the WebAssign reading sheet is completed for Monday.
Have a great weekend! The next scribe will be Korri H.

SUGAR, Spice and Everything Nice

In Chemistry today, we got started right away on part B of the Beverage Densities lab. Each of the groups went to their lab stations and decided what two beverages they wanted to use in the experiment. We could choose orange juice, apple juice, lemon-lime gatorade, cranberry juice or diet cola (which wasn't suppose to be diet! Jeeeeez Mr. Lieberman!) :) My group chose gatorade and diet cola.

Next we used the same procedure as we did in part A to find the mass of the liquid. We drew up 5mL of the gatorade and massed it on the scale. Then we subtracted that mass from the mass of the empty beaker to get the mass of the gatorade. We did the same thing for the diet cola and then calculated their densities using the formula d= m/v. We found that the gatorade had a higher density than the diet cola because there is more sugar in the gatorade.

Every group finished their labs early today, so Mr Lieberman kindly let us work on our post lab questions. Part of the post lab is making a graph like we learned how to do on Excel.

NOTE: For post lab question #2 you are suppose to find the actual value and in #3 you are suppose to find the theoretical value. Mr. Lieberman clarified this towards the end of class. Remember that the formula for calculating percent error is the absolute value of (estimate value - actual value) / actual value * 100.

Good luck with the post lab questions and enjoy sleeping in tomorrow morning!!

Mollie M.

Oh and the scribe for tomorrow is ....................................................................................................... Korri H.

Ps: sorry for there not being any pictures to enhance your visual interest, but every picture I downloaded said there was an error :'(

Colorful Concentrations

Today in class we started off by turning in our Density of Pennies Lab. We then went over the concept of percent error and how to calculate it. The formula to find the percent error is theoretical value subtracted from the actual value, then divide that by the theorectical value and then that answer is multipled by one hundred. Mr. Lieberman said this is important to know and that we will be using it continually throughout the year.



After that, Mr. Lieberman showed us a demonstration using salt water, two different types of beads, and isopropyl alcohol in a plastic bottle. When Mr. Lieberman shook the bottle, the two liquids combined and the beads were everywhere, but then the white beads floated to the top and the blue beads sunk to the bottom. As the water and alcohol began to seperate, the white beads slowly moved down and the blue beads floated up and the two met in the middle. The point of the demonstration was to show how density effected where the four substances stayed in the bottle and what happened when they were mixed together.



For the last half hour of class we started the Beverage Density Lab. Mr Lieberman showed us how to use the pipet -not with your mouth :). Then we began the lab by placing the beaker on the balance and "rezeroing" the balance. Next, everyone poured each of the different concentrations- 0%, 5%, 10%, 15%, and 20%- into idividual beakers and took them back to the lab tables. Yes, the mixtures were very pretty colors but not to be mistaken for Gatorade : ) We then used the pipet to measure out 5 mL, not 10 mL, of each concentration and put it in the big beaker to measure the mass. Our group's data showed that the mass of the concentrations increased as the amount of sugar in each mixture increased. We then used the mass we measured and the volume of 5 mL to calculate the density. Tomorrow we will continue the lab and do part B. The finished lab will be due Wednesday and Mr. Lieberman explained that we will need to do another graph for question number one of the post-lab questions.

The next scribe is Mollie M.