Logarithmic practice problems

Practice logarithms below using the "rules" that you have just learned. Answers are provided (but try doing them on your own before peeking!)

Problem 1. Suppose that you test pineapple juice and find that the hydrogen ion concentration is [H+] = 0.0003 M. Find the pH value and determine whether the juice is basic or acidic.
Solution.

Problem 2. You test some ammonia and determine the hydrogen ion concentration to be [H+] = 1.3 x 10,sup>-9 M. Find the pH value and determine whether the ammonia is basic or acidic.
Solution.

Problem 3. Before fertilization, an egg cell has a calcium concentration of 1.2x10-14. When the sperm penetrates the cell membrane at the instant of fertilization, the calcium concentration increases to 2.4 x 10-5. What is the magnitude of the increase in calcium in the cell?
Solution.