pH Scale

pH Scale

Author: Nathan Lampson
This lesson will introduce the concept of pH, acids and bases.
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Introduction to Psychology

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You've probably heard of acids - corrosive liquids that eat through desks.  Well, in order to measure how acidic a substance is scientists use something called the pH Scale.  The pH scale ranges from 0-14 but some very strong acids can have pH levels below 0.

The pH scale displays the amount of an atom called hydrogen ions.  The greater the concentration of hydrogen ions a substance has, the more acidic.

On the other end of the pH scale are a different type of extreme substance called bases.  Bases can cause burns and be corrosive just like acids.  The concentration of a base is determined by the number of molecules called hydroxide ions.  If a substance is considered very basic it might have a pH of 14.

If the concentration of hydroxide ions and hydrogen ions is equal, a neutral pH of 7 is achieved. Water has a pH of 7 and is neither an acid or a base.