pH stands for the "power
of Hydrogen" and measures the concentration of hydrogen
ions in a solution, such as water. What is a hydrogen
"ion?" It is an atom of hydrogen that has lost its
electron. In water, hydrogen automatically gives up its electron to
pH varies over an enormous range of values. Thus,
it has to be measured on a scale
that is different from other measurement scales. A solution
with a pH=0 has 10 times more hydrogen ions than a solution with
a pH=1 and 100 times more hydrogen ions than a solution with a pH=100.
This "logarithmic" type of scale is commonly used in chemistry
and physics to specify the value of numbers that have an extreme
range of values.
pH or the concentration of hydrogen ions in water
is largely determined by the environment surrounding a lake, river,
or stream. Changes in pH can be the result of natural phenomena
or man-made events. A change in pH can disrupt the life cycles
of all organisms (animals and plants) and lead to their deaths if
the change is hydrogen ion concentration is too extreme.
important is pH?
Is water quality affected by pH? What happens to organisms
when pH changes? What causes a change in pH? In this
unit, you will discover answers to these questions.