## Wednesday, August 17, 2011

### First Week - Density and Safety

Monday was a get-to-know-you sort of day. Students started with an informal survey and drew a picture of themselves that I will use to help learn their names (I am terrible at names). I familiarized the students with classroom procedures, discussed homework and classwork, and let them know how class was going to run.

We have made sure that everyone had a good handle on density in regards to definition, math and formulas, and what it actually means. Density is how close together the particles are in a substance. If they are close together the substance is more dense. If the particles are far apart, the substance is less dense. I do not float in Lake Anna, but I do float in the ocean - therefore I am more dense than Lake Anna and less dense than the ocean.

Students made predictions for a density column including corn syrup, water, mouthwash, baby oil, and vegetable oil. Things that are more dense-sink, things that are less dense-rise to the top, things with similar densities-mix. Then I poured the liquids in a randomly asked for order and students looked at how the layers formed because of the differences in density. They also fielded oral questions as the demonstration was performed. Here is a photo of a similar demo.

Today we are going to cover lab equipment and do a fun gummy bear lab. Here is a good handout to review them. Students will try on their own to id the equipment before I tell them what everything is.

Last night's homework was box A&B on the blue sheet. Tonight it is box C&D. Tomorrow is Thursday so there is a syllabus/density quiz and the safety test will be on Friday.