of the activity:
calcium is turned into alkaline by the body to neutralize pH in pop, thus
depleting bone calcium. This experiment
is designed to test the pH level in various beverages to identify the beverage
with the lowest pH level. The lower the
pH, the more likely the beverage will aid in bone calcium depletion.
Note: It may be more cost-effective to purchase
2-liters instead of 6-packs of pop.
Also, even though the students are conducting the experiment
individually, have students share a pH meter in groups of 6 unless you have
opted to use the pH strips.
Lay out all the materials for the students. Mark the inside of the plastic cups at the
same level so the students pour the same amounts of pop in the cup for
testing. Make sure not to open the pop
before the experiment. The results may
change depending on the flatness of the pop.
students to test Coca-Cola, Pepsi, Mountain Dew, Sprite, Orange Soda, Root
Beer, water, or milk. Note: Please make sure that the class is
evenly dispersed with the different types of beverages. Ask students to predict the pH levels of
their respective beverage. Write some
of the predictions on the chalkboard.
Have the students fill in the “Hypothesis” and pH level guesses on
their Lab Sheets.
each student gather their 3 cups and pour their respective beverage into
the first cup up to the designated mark.
To test the pH level, place the pH meter or pH strips in the
beverage and wait 10 seconds or until the numbers or color stops
changing. Have students record the
number that is on the pH meter or the number that is associated with the
color on the pH strips. The student
should repeat this process two more times and take the average of the
results. Note: Since the students will be sharing a pH
meter within the group, have each student wait to open their pop until it
is their turn to test the pop using the pH meter.
students complete the experiment using the directions outlined on the Lab
Sheet and answer the follow-up questions.
- At the
conclusion of the experiment, have each student present their findings and
discuss their conclusions.