Procedure
1. Water as a universal solvent
a. Put about 0.5 grams of the following substances into six separate test tubes: NaCl, sugar, gelatin, margarine, ethanol.
b. Add 1 mL water to each test tube and shake vigorously to dissolve the substance. To substances that did not dissolve, add another 1 mL of water and shake again. Add another 1 mL to the solids that still not dissolve and shake again.
c. Repeat the solubility test using acetone instead of water.
2. Water as a good medium for biochemical reactions
a. Mix about 0.1 gram of dry, powdered citric acid and sodium bicarbonate (NaHCO3) in a dry test tube. Observe if a chemical reaction occurs.
b. Add about 10 mL of water to the mixture and note what happens
I. Find the solubility in WATER and solubility in ACETONE of the following:
1. NaCl
2. Sugar
3. Gelatin
4. Margarine
5. Ethanol
II. What are the reaction of Citric Acid and Sodium Bicarbonate?
In the presence of water, citric acid and sodium bicarbonate (aka baking soda) react to form sodium citrate, water, and carbon dioxide.
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