1. Lay graduated cylinder on its side in tub of water Fill with water
Lay graduated cylinder on its side in tub of water Fill with water. Tilt to remove all air bubbles.

2. Fill test tube #1 with 8 mL of yeast solution with sugar added.
+ NO SUGAR
Yeast
+ SUGAR
Fill test tube #1 with 8 mL of yeast solution with sugar added.
Fill test tube #2 with 8 mL of yeast solution with NO sugar added.
Screw on tops and submerge in water tank.
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3. Invert graduated cylinder keeping opening under water.
Keep test tube at angle to keep yeast liquid away from hole.

4. Collect gas escaping from test tube. Start timer
Collect gas escaping from test tube. Start timer. Record level on graduated cylinder at 1 minute intervals. Fill in data table.
Do this for BOTH test tubes.