Which soda does the most damage to tooth enamel? Limestone stands in for enamel in this experiment because it reacts to acid the same way. You soak 40 grams of limestone in each soda for 24 hours.
You also test the pH (acid level) of each soda with pH paper. After soaking, you dry the limestone and weigh it again. The weight lost shows how much each soda dissolved.
The results hold a surprise. Diet sodas often dissolve more limestone than their regular versions.
Hypothesis
The hypothesis is that Pepsi will be the worst because it has a lot of acid and acid is bad for teeth enamel.
The pH scale runs from 0 to 14 and measures how sour or bitter a liquid is. In this experiment, you test the pH of each soda with pH paper. You also soak 40 grams of limestone in each soda for 24 hours and weigh what remains.
When an acid slowly eats away at a solid material, that is acid erosion in action. Limestone stands in for tooth enamel here because it reacts to acid the same way. You soak 40 grams of limestone in each soda for 24 hours, then dry and weigh it again. The weight lost shows how much each soda dissolved. The results hold a surprise — diet sodas often dissolve more limestone than their regular versions.
Method & Materials
You will test the pH of different sodas, measure and record the amount of limestone, and wait 24 hours to measure the effect on your teeth enamel.
You will need pH Hydrion paper, granulated limestone, a coffee filter, a graduated cylinder, and cups.
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The experiment showed that Pepsi was not the worst for your teeth enamel, as the hypothesis suggested. Diet Root Beer was the worst, and Dr. Pepper was right behind it. The best soda to drink was Sprite, although its diet version didn't do so well.
Why do this project?
This science project is interesting because it shows that diet sodas are actually worse for your teeth than regular sodas.
Also Consider
Experiment variations to consider include testing different types of sodas, testing different amounts of limestone, and testing different lengths of time for the limestone to soak in the soda.
Full project details
Additional information and source material for this project are available below.
