How Do You Rate?

Challenge #4: Lab Worksheet #3

Station Three: This Is A Cool Station!

Date of Investigation:

Name of Scientist:

Name of Recorder:

Purpose: The purpose of this lab investigation is to observe how changing the temperature of water will change the rate at which an Alka-Seltzer tablet will react.
Hypothesis: If the temperature of the water is higher then the rate at which an Alka-Seltzer tablet reacts will (increase or decrease).

Materials:

• Safety glasses and aprons
• Three large beakers containing water at different temperatures
  
  • Label beaker one for the cold water
  • Label beaker two for room temperature water
  • Label beaker three for warm water
• Three equal pieces of Alka-Seltzer (or other effervescent tablet)
• One bottle of distilled water
• One stopwatch
• One thermometer
• Spoon Two equal pieces of chalk (approx. 2 cm)

Procedure:

1. First read ALL of the procedure before you begin.
2. Place one piece of effervescent tablet into the small beaker labeled one.
3. Take the temperature of the cold water and record the observation in the Observation Table below.
4. Add cold water carefully to the 10 mL line of beaker one.
5. Start the stopwatch.
6. Stop the stopwatch when no more bubbles are produced.
7. Record the time of the reaction (in seconds) in the Observation Table on the following page.
8. Pour the contents of this beaker down the sink.
9. Repeat steps 2 to 8 using room temperature water (beaker two).
10. Repeat steps 2 to 8 using warm water (beaker three).
    
11. Clean up your station. Complete the checklist below before proceeding to the next station.
    • Rinse all beakers with a little distilled water.
    • Wash the counter space.
    • Wash your hands.