A pH scale is a measurement system used to indicate the concentration of hydrogen ions in solution; ranges from 0 to 14. In other words, the pH scale shows the acidity or basicity of a substance. 7 is when the pH of something becomes neutral, for instance, water. The concentration of hydrogen ions determine the acidity or basicity, so water has a concentration of 1x 10 to the negative seventh power. A pH of 6 is a concentration of 10, and gets 10 times more concentrated as the pH gets decreased by 1. A pH of 8 has the concentration of 1/10, and gets 10 times less concentrated as the pH gets increased by one.
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