Archive for August, 2007

Models of bread and cheese

Wednesday, August 29th, 2007

We're having the most fun with carefully sectioned compressed cellulose sponges. TraderJoes sells a version, oui, at fifty cents a sponge. Cutting lengthwise into three gives thirty six in a package. Like watching a strip of matzoh inflate into a slice of bread. The biology ...

Instructables and LN2 ice cream

Monday, August 13th, 2007

Okay. First, Instructables is one of the coolest learning sites ever.   Instructables are like multimedia how to recipes.  Are there any other good how-to wikis? wikiHow jumps to the top of the list on Google, but no entry about liquid nitrogen ice cream.  Let me know if ...

Solution chemistry

Tuesday, August 7th, 2007

The demos today are all about solutions and their properties. The easiest two are heat of solution. Ammonium nitrate portable cold pack and calcium chloride portable hot pack make the point quite nicely. Handing them around the room is safe and makes for a tactile demo. Supersaturation of sodium ...

Electrochemistry

Friday, August 3rd, 2007

The demos of the summer school chemistry class were based on the topic of electrochemistry. Half cells and salt bridges in a row on the lecture bench. The hydrolysis apparatus is connected to a six volt battery. It should split enough water for the professor to get his test ...

NanoD

Wednesday, August 1st, 2007

States of aggregation and reaction rate.  Lycopodium explosion. Seeing speckle with green laser and cell, and water and silver colloid. Making particles chemically.  Lead iodide precipitation on cooling. Show news stories.  Rumors of 5 kg. nanotubes shipped in kraft paper. Methanol and platinum and platinum black.  Danger.  Danger. No photos yet.