The term pH is taken from the German word ‘potenz’ meaning power and H, the chemical symbol for Hydrogen. So when you are measuring the pH level, you are finding out the amount (or power) of Hydrogen ions present.

This measurement is important because it can tell you whether water is acidic, basic or neutral. Below is a scale that shows you some pH values of substances you are probably familiar with.

Aquatic organisms live best in waters that have a certain pH value. Scientists study the pH values of water because a changing pH could indicate increased pollution or some other environmental factor.

Polluted rain can be very acidic and affect the environment in a negative way. When coal or gasoline is burned as a source of fuel, the sulfur dioxide (SO2) and nitrogen oxides (Nox) released in the smoke mix with water vapor in the air to form sulfuric or nitric acid. The water then falls to the ground as acid rain. If the rain is too acidic it will kill plants, fish and other organisms in the environment. Below is a scale that shows the pH ranges that support aquatic life.

Questions: Click on the question to see the answer

Where does sulfur and nitrogen in the atmosphere come from?

As the pH value decreases does the water become more basic or more acidic?

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A chemical compound, usually a liquid that is capable of transferring a hydrogen ion in solution. Any substance with a pH value of less than 7.

Plants or animals that live in water.

Any chemical capable of accepting or receiving a hydrogen ion from another substance. Any substance with a pH of more than 7.

Neither acidic nor basic. Water is neutral with a pH of 7.