BCA part two

Half way through the unit.  One thing we’ve noticed about BCA is that it is much easier to find the misconception that students have about what goes on in a reaction and correct it right away.

Lab on Monday.  I like to blend the old with the new and have, therefore, dusted off an oldie.  Mixing two solutions together to form a precipitate and filter.  From the mass of the precipitate, they have to find the Molarity of the original limiting reactant.

As this is my first time with BCA, every time a student comes in with a question, I’m making a note of what to change for next year.  the latest one is to remember to stress “subtract reactants” and “Add products”

bce example

I’ll see how the lab goes on Monday.


New Things happening in Chemistry this Week – BCA, Baby

In my ever maddening quest to make chemistry less like a math class and more like “science” I’m going to try something new, again.

Last summer at the BCCE, I saw a great presentation about a new way to do stoichiometry problems called BCA.  It’s patterned after the ICE method of determining equilibrium constants developed (as far as I can tell) by Larry Dukerick at Arizona State as part of their Chemistry Modeling Program (link to slideshare presentation).

I, of course, am one to jump into the deep end of the pool without checking on the temperature of the water am going to give it a try with just a little planning

OK, maybe a lot of planning.  I have been modifying most of my class discussion to focus on the particle view.  Always relating back to the mole and how the mole and particle relate.  Labs are becoming more inquiry based.

I’m also trying another new idea.  I’m making students guess if they don’t know an answer.  This way, I can determine just how much they don’t know, and also it has lowered their inhibition about contributing to the classroom discussion.  A few socratic questions asked by me has been overall successful in leading the students to develop their own understanding of the many concepts while allowing them to be more involved in the discussion.

Right now, I’ve got my collegue going over the plan of attack for this thing.  If it passes muster, it’s 100 percent go for this year.

Biggest fear is do I abandon traditional stoichiometry or not?

Like I’m A Kindergarten Teacher

A few years ago, I worked in a school that allowed every teacher that taught science to sit down for several days.  When I say every teacher I mean teachers from Kindergarten through high school.  It was an amazing experience and we were able to get a lot done.

What I remember the most was when the Kindergarten teacher would shake her head and say “I don’t teach science.”  we only talk about the seasons, the weather, how we breath faster when we run, sweating, laughing, and that batteries can go dead.”  We told her that was science.  She still shook her and said that she didn’t know how it was science, when she didn’t think it was science.

I think about this a lot; especially while reading some of the articles in Chemical and Engineering News and Physics today. I start reading the article, and then just shake my head and wonder how is what I teach my chem and physics students ever going to help them to understand some of the theories based upon these ideas?  I don’t even get some of it.

Maybe that’s what is needed.  A workshop that pairs research scientists with science teachers where all they do is discuss a couple articles published in a professional journal and trace the theories back to what is taught in a high school chemistry or physics class.

There is a subreddit titled “explainlikeimfive.  Perhaps, it could be something like that.  Except more like explainlikeimteaching it to a five year old?