Example: Calculate the pH of a buffer solution that initially consists of 0.0400 moles of ammonia and 0.0250 moles of ammonium ion, after 20.0 mL of 0.75 M NaOH has been added to the buffer. Ka for ammonium ion is 5.6 x 10 -10.
There are two types of bacteria. Aerobic bacteria live with oxygen, love the company of food particles in the mouth and feed on sugar. Anaerobic bacteria exist without oxygen and feed off dead skin cells and other bacteria.
Hundreds of different types live on our teeth, gums, tongue and other places in our mouths. Some bacteria are helpful. But some can be harmful such as those that play a role in the tooth decay process. Tooth decay is the result of an infection with certain types of bacteria that use sugars in food to make acids. Over time, these acids can make a cavity in the tooth.