PH Levels of Various Types of Soda Pop

 PURPOSE

The purpose of this experiment was to determine the pH level in various types of soda pop.

I became interested in this idea when I was drinking a soda and I wondered what caused its tart taste and acidy fizz. 

The information gained from this experiment could help consumers know what kind of soda pop to buy that won’t destroy their bone calcium and tooth enamel as much as others. 

HYPOTHESIS

My hypothesis was that colas like Coca-cola or Pepsi would have lower pH than the other pops.

EXPERIMENT DESIGN

The constants in this study were:

• Temperature of pop

• The amount of soda-pop in each container

• The type of pH measuring meter

• Container the soda is put in

• How long the meter is put in the soda

• Type of container the pop was held in

The manipulated variable was the kind of soda pop.

The responding variable was the pH level. 

To measure the responding variable I used a digital pH-measuring meter.

MATERIALS

QUANTITY	ITEM DESCRIPTION
3	12 oz. (355 ml.) Coca-Cola
3	12 oz. (355 ml.) Pepsi cola
3	12 oz. (355 ml.) Mountain Dew
3	12 oz. (355 ml.) Sprite
3	12 oz. (355 ml.) Orange soda
3	12 oz. (355 ml.) Root Beer
1	pH meter
1	Measuring cup (ml)

                                        PROCEDURES

1. Collect items for experiment.

a. Three cans each of Coca-Cola, Pepsi, Mountain Dew, Sprite, Orange soda, and Root Beer.

b. Digital pH measuring meter

c. Measuring cup (ml)

2. Label each group of three pops a-f.

3. Take a can from group A and measure out 100 ml. of the pop in a measuring cup.

4. Next put pH meter in the soda pop that’s in the measuring cup and wait for about ten seconds. After the numbers stop changing, read meter. Record data.

5. Triple test each can, so do this test two more times.

6. Repeat step 3 - 5 for the rest of the cans in-group A. 

7. Average the results for all the cans in this group.

8. Repeat steps 3 - 7 with another group like B.

9. Repeat steps 3 - 7 for the rest of the groups C - F.

RESULTS

The original purpose of this experiment was to find the pH levels in various types of soda pops.

The results of the experiment were that Root Beer had the highest pH at 4.24 followed by Sprite at 3.29 and Mountain Dew at 3.27.  The lowest scores were Orange at 2.90, Pepsi at 2.61, and the one with the lowest pH was Coca-Cola at 2.52. 

CONCLUSION

My hypothesis was that colas like Coca-Cola or Pepsi would have lower pH than the other pops.

The results indicate that this hypothesis should be accepted because Coca-Cola and Pepsi had lower pH than all the other pops. 

Because of the results of this experiment, I wonder if the amount of carbonation would affect the amount of pH.  For example, if the pop was forced to be “flat” would that affect the pH.

If I were to conduct this project again I think I should use the reference solution for the pH meter more often to make sure it was still reading right during the experiment.

I also could have tested more brands of pop to tell the pH of other pops that people might like, for example Shasta pops and Sam’s Choice.

I should have tested different types of pop like Mountain Lightning, which is almost the same as Mountain Dew and I should have checked for a difference.

Researched by --- Marshal N