Chemistry of Tooth Decay and Prevention

Tooth decay is a major health concern.

For more than 50 years we have been adding fluoride to our water supplies and toothpaste to help prevent tooth decay.

It is estimated that this fluoridation of drinking water alone has resulted in a 25% decrease of tooth decay in children and adults.

What causes tooth decay and how does fluoride prevent tooth decay and cavities?

 Learn about the chemistry of tooth decay and how to prevent it in the March 2021 issue of AUS-e-NEWS. Subscribe to AUS-e-NEWS for free at https://www.ausetute.com.au/ausenews.html

pH After Mixing Weak Acids

 Acetic acid is a weak acid (K_a = 1.8×10^-5).  The pH of 100 mL of 0.10 mol L^-1 acetic acid is 2.9.

Hydrocyanic acid is a weak acid (K_a=6.3×10^-10). The pH of 100 mL of 0.10 mol L^-1 hydrocyanic acid is 5.1.

But what is the pH of the resultant solution if you mixed these two weak acids together?

AUS-e-TUTE has just added new resources to help you understand how to calculate the pH of solutions after mixing weak acids together. AUS-e-TUTE Members should log-in to access the new tutorial, game and test with worked solutions.

If you are not yet an AUS-e-TUTE member, you can access the "free-to-view" tutorial at https://www.ausetute.com.au/phmixwa.html