Monday, April 14, 2008 - 4B

Quiz on fractional distillation.

Students corrected other students papers with red pen, handed them back to owners, and then handed them in bin.

Next identification labs will be Crystal Test, Acid Test, Flame Test
Went over how to set up crystal test in petri dish.
Using an overhead marker, draw lines on the bottom of the petri dish to divide the dish into quadrants. Label the quadrants 1 for CuSO4, 2 for NaCl, 3 for CaCO3/MgCO3, 4 for KCl. Students either used the solutions I mixed up (shaking first) and put 4-5 drops of each solution in the correct quadrant, or put a few drops of water in the quadrant, added some powder, and then mixed to dissolve.

Students put petri dishes in box lid to evaporate to form crystals for next class.

Students put neat data table (drawn with ruler) in notebooks for next time.

Sink or swim exercise. Density is a measure of how much mass is packed into a given volume. The density of fresh water is 1.0 g/cm^3. If an object is more dense than water, it will sink. If an object is less dense than water, it will float. Put several objects into aquarium and tested for sink or swim.

Equation for density is density = mass/volume.

Went around room giving density problems.

Played a round of science trivia.

Collected notebooks for students who did not hand them in last period.