The effect of acid on The effect of acid on

tooth decaytooth decay By Ernest Rutherford and Marie Curie

PurposePurpose The purpose of this experiment is to The purpose of this experiment is to

determine the effect of different determine the effect of different concentrations of vinegar on the concentrations of vinegar on the mass lost in human teeth.mass lost in human teeth.

Materials and MethodsMaterials and Methods

3 styrofoam cups3 styrofoam cups waterwater 3 human teeth3 human teeth vinegarvinegar digital scaledigital scale

ResultsResults

Time (hours) Mass of tooth in water (g)

Mass of tooth in ½ water and ½ vinegar (g)

Mass of tooth in vinegar (g)

0 0.538 0.519 0.442

2 0.531 0.511 0.410

5 0.529 0.499 0.391

12 0.529 0.570 0.359

24 0.522 0.422 0.324

Table 1. Mass of teeth in different concentrations of vinegar over 24 hours.

ResultsResults

Time (hours) Total mass percentage lost in water (%)

Total mass percentage lost in ½ vinegar ½ water (%)

Total mass percentage lost in vinegar (%)

24 3 14 31

Table 2. Percentage of tooth mass lost after a 24 hr period in different concentrations of vinegar.

Qualitative ObservationsQualitative Observations

Vinegar

- Tooth Decay

- Shriveled

- Yellow

- Cracked

Water

- Normal colour

- Smooth

- No damage

½ Vinegar ½ Water

- Bright White

- Shriveled

- Bumpy

- Chipped

Research SourcesResearch Sources

http://www.britannica.com/EBchecked/topic/3235/acetic-acid-CH3COOH - William H. Brown (Proffessor in Chemistry, Beloit College)

http://www.mayoclinic.org/diseases-conditions/cavities/basics/causes/con-20030076 - Roger W. Harms M.D. (Director of Mayo Clinic)

Explanation of ResultsExplanation of Results

Independent variable – What is vinegar?Independent variable – What is vinegar?

Acetic acidAcetic acid

moleculemoleculeWaterWater

moleculemolecule

Explanation of ResultsExplanation of Results

Ca5(PO4)3OH(s) + H+(aq) → Ca5(PO4)3+(aq) + H2O(ℓ)

HydroxylapatiteHydroxylapatite

ImplicationsImplications

ACID

Thank You!Thank You!