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What is the pH scale?
The pH scale typically runs from 0 to 14 and is a way of measuring how acidic or alkaline a solution is. It is a logarithmic scale, so a change of one represents a ten times increase or decrease in acidity or alkalinity. A neutral solution has an equal number of hydrogen and hydroxide ions; this is usually a pH of 7, but can vary slightly depending upon temperature. A pH from 8 to 14 indicates alkalinity with 14 typically being the highest alkalinity. A pH from 0 to 6 indicates acidity with the lower number being more acidic, hence 0 is the highest acidity.
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