Although you may
hear the term thrown about frequently, few people actually have
an in-depth knowledge of just what pH is. Affecting nearly every
solution in the world around us, pH has an impact on everything
from the weather to personal health. However, the answer to the
question, “What is pH?” is not nearly as complicated
as its effects. Essentially, pH is a measurement of the concentration
of hydrogen ions in solutions. What pH is an abbreviation of is
the phrase “potential of Hydrogen.”
Ranging from values
of 0 to 14, what pH is used to measure is the acidity or alkalinity
of a substance; that is, how acidic or how basic (caustic) it is.
A score of 7 is perfectly neutral, while numbers below 7 are acidic,
and numbers above 7 are basic. Although there may not seem to be
much difference between the numbers, what the pH of a substance
is can make a huge impact. For example, human blood has a pH between
7.35 and 7.45, and even a tenth of a variation outside of this range
can result in death. Further, the body’s pH being off can
result in numerous health problems.
So, just what is
pH technically? Well, a liquid with a pH of 4 would have 1 x 10-4
moles of hydrogen ions. A pH of 10 means the solution has 1 x 10-10
grams of hydrogen ion (for hydrogen, 1 mole is the same as 1g/L).
In the most technical sense, the answer to “What is pH?”
is: pH is the negative logarithm of the concentration of the hydrogen
ion in a substance. However, in laymen’s terms, what pH is
meant to measure is simply the acidity or alkalinity of a substance.
