Stoichiometry that might work...

WHAT AM I DOING TO HELP KIDS ACHIEVE?

HOW DO I KNOW WHEN THEY ARE THERE?

WHAT IS THE EVIDENCE?

     So I did a quick stoichiometry starter.  Given 61 students, kids had to calculate the exact amount of packages of Hershey bars, marshmallows and gram crackers that I would have to buy and how much it would cost.  Students pretty much nailed it.

     I then did a lab "No Leftovers" by Stephanie Kimberlan.  It is a TIMU lab.  Students have several mole to mole and gram to gram ratios they must calculate (Al and Copper(II)chloride).  To make a long story short, the calculations went well and so did the lab.  It was very visual and many kids succeeded who typically say they hate math.  I "tweaked" it a bit (instead of grams I made a solution of the copper(II)chloride and had them calculate mL as well).  I told them they could calculate the ratios using cross multiplication, proportions or factor labeling....as long as I could see and understand their work.  It was extremely visual and really steared the kids to the mole to mole concept in the balanced equation. (The above pictures are "before" and "after").

     This is a tough time of year to teach.  We are done with tests, students are getting ready for summer and freaking out over AP tests.  We had a star party Thursday night.  It worked out amazingly well.  We saw Venus, Jupiter and had some great shots of the moon.  I had some kids I could barely pull away from the telescope and they all tried to take pictures through the eyepiece with their cell phones.  Not the traditional kind of science but I will take anything I can to get kids excited.

     Coming up next...Hess's law and more stoichiometry...I'll keep you posted....

Not bad so far....

WHAT AM I DOING TO HELP KIDS ACHIEVE?

HOW DO I KNOW WHEN THEY ARE THERE?

WHAT IS THE EVIDENCE?

     I started doing heat diagrams as suggested by the American Modeling Teacher's Association.  Essentially, students identify energy as thermal, chemical or phase energy.  They examine and endo or exothermic reaction and draw where the energy is going.  They can also do the same in reactions where there is a phase change.  Why do I mention this?

     Every year when we do the heat of fusion of ice and the specific heat of a metal labs I almost always have a handful of students use the wrong mass or temperature change in the heat equation.  They would constantly get confused between the system and the surroundings....until now.  I went through the heat bar diagrams and this time I have not had one student use the wrong mass or temperature.  I would like to claim credit, but honestly I am not that good.  The AMTA curriculum is.  Lesson learned....

     This week in academic we are starting with stoichiometry.  First, they will have to tell me how many marshmallows, chocolate and gram crackers are needed for everyone to get a smore.  If they get it right, then they each get a smore.  I'll keep you posted....

How to See what the Metal is doing...

WHAT AM I DOING TO HELP KIDS ACHIEVE?

HOW DO I KNOW WHEN THEY ARE THERE?

WHAT IS THE EVIDENCE?

     So here is the plan....for the most part, the ice lab went well.  Students did a good job of finding the heat of fusion of ice.  So here is the next challenge.  I told them that provided with certain materials, they must find the specific heat of a metal.  Tomorrow, we are going to go over their possible ideas and see if they can get data to find the specific heat of a metal.

In Academic we are doing types of reactions, classifications and balancing. They are doing particulate models and the models are going better than the classification. That is the first time I have had this problem and it is a nice problem to have. I have been using the curriculum from the American Modeling Teachers Association and it is working well. It will be really interesting when I use Stephanie Kimberlin's TIMU activity for stoichiometry to see how it goes. I may also follow up with AMTA material. I'll keep you posted. I have decided the most important thing now is to keep plowing ahead no matter how crazy it gets during 4th q....

Iceberg Part II

WHAT AM I DOING TO HELP KIDS ACHIEVE?

HOW DO I KNOW WHEN THEY ARE THERE?

WHAT IS THE EVIDENCE?

     So I started the heat of fusion lab.  I had students get data.  Then I posed the question, "How could you figure out how much energy it takes to melt some ice with this data?"  I asked students what they would need to know to use the data to solve the problem and we came up with a list of questions.  Now we started using the American Modeling Teacher's Association heat model with the bar graphs.  Students i.d. the "system" and look at what is happening with the energy due phase, chemical or thermal energy.  Hopefully, after doing this they won't confuse which mass to use in Q=MCdeltaT.

    A piece of good news...I had student build "lego calorimeters" from a current J. Chem. Ed. article.  One student who did a really good design explained that on the way home he lost the resistor so he ripped apart an old transistor radio for a similar resistor and then thought it might be nice to have a switch so he pulled that off another broken device.  I was pretty impressed with his ability to scrounge and get it done.  Building your own chemical instrumental device and scrounging to make it work is in the spirit of a true analytical chemist.