In Chemical Mystery #7, a can of Coca-Cola was observed to sink in one container of water and yet float in another! This trick made use of the fact that the density of water changes with temperature.
Q: Does an unopened can of soda pop float or sink in water?
A: It depends!
See if you can figure out what is happening in this twist on the classic floating-and-sinking soda can experiment.
It's been a few days since my summer break began. I have had a few days to decompress, relax, and think about my next post. I have been planning to write about concept mapping since the end of our first semester. I first recognized the effects of concept mapping in the classroom when I read Shannon Bowen's blog post last December.
During our review since last week, resonance was labeled as one of the most tricky concepts (along with electron pushing in my opinion), despite lots of practice and instruction. My teaching sequence consists of defining and providing examples of conjugation (after learning about hybridization), delocalized electrons, and finally pushing electrons if conjugation exists. I remember from teaching at the college level that resonance was also a tricky topic for many undergraduates.
Solution to Chemical Mystery #6 is presented. Also, concepts related to the chemical can crush demo are briefly discussed.
Can you figure out how this experiment works?
I recently stumbled across a blog about the use of BCA (Before Change After) tables for stoichiometry written by Lowell Thomson. I was thrilled to discover ChemEd Xchange! I wanted to share my journey, spurred on by my students, into the extensive use of the BCA approach in AP and
We’ve all seen and use the so-called Aufbau Diagram. It is a mnemonic used to remember the order of “filling” of atomic orbitals during the construction of the ground state electron configurations of the elements. The presentation of this diagram is largely disconnected from any physical meaning. Here’s what we tell our students: “Memorize the diagram, learn to use it, and you’re guaranteed to get the right answer.”
A complete understanding of why each element has a particular electronic configurations is a very complex subject. Even so, some confusion regarding the electronic configurations of the elements may be alleviated by looking at the physical properties of the electronic orbitals.
Previously I wrote about taking part in a district-wide high school blended learning pilot. You can read about it here. I received my Chromebook cart near the end of February/beginning of March. A little late but just in time for the periodicity unit I was planning as a blended unit. The following is a breakdown of how I designed the unit.
