Labs & Group Activities - SOL 2

1. Water Activities - Properties of water

Obj: Demonstrate properties of water to enhance instruction, review scientific methods

Materials: water, cup/plate, salt, beaker, hot plate, ice cubes, sharp probe, probeware (temp/conductivity/pH), graduated cylinders, triple beam balance

Methods: fill cup with water, place plate over it and invert (plate should remain suspended) - discuss adhesion and cohesion - break vacuum with probe

Beakers with equal amount of water and allow them to come to room temp. Weigh ice cubes, pour equal amount of hot water in graduated cylinder. Add ice to one beaker, hot water to the other - record changes

Measure conductivity of water, add salt and observe patterns of change

2. pH Lab - Qualitative (to Quantitative Analysis)

Obj: Perform qualitative analysis of unknown substances using red, blue and yellow litmus papers.

Materials: unknowns, litmus papers, forceps, "trash cans", safety goggles, pH probe/probeware

Methods: dip litmus papers in liquid (do not allow forceps to touch), record results in chart

Analysis: discuss results, estimate pH, reveal unknowns, discuss bias/errors

3. Yeast and Anaerobic Respiration

Obj: Qualitative (and quantitative) analysis of carbon dioxide production of yeast when mixed with a variety of substances and water (both warm and cool)

Materials: Yeast, substances - sugar, brown sugar, flour,...) measuring spoons, graduated cylinders, ziplock bags, test tubes, beakers, stoppers with holes

Methods: mix 1/4 teaspoon yeast with teaspoon of substance, add water and mix again. Place in ziplock bag and get rid of air. Wait.

Analysis: examine bags for bubbles, compare size of bubbles to determine comparative rates of gas production.

Mix in test tube, fill completely and invert in beaker of water of similar temperature. As gas is produced it will collect in the tube, while water will be forced out of holes in stopper. Make sure to mark starting volume of gas!

4. Carry-over of Zen Garden (chlorophyll/salt tree) - concepts of solvents, organic and inorganic chemistry, absorption/transport by cohesion and adhesion/transpiration...