Example #1 a) Calculate the pH of a solution with a hydrogen ion concentration of 3.98x10-5 .

b) The water in a swimming pool should be maintained at a pH of 7.5. What is the hydrogen ion concentration of the water?

Example #2a) Normal conversation registers at about 40 decibels. Normal breathing registers at

about 10 decibels. How many times more intense than breathing is normal conversation?

Example #3a) The Northridge earthquake of January 1994 registered 6.9 on the Richter scale. What

would be the magnitude of an earthquake 100 times as powerful as the Northridge quake?

b) How many times more powerful than the Northridge quake was the San Francisco earthquake of 1989, which registered 7.1 on the Richter scale?