An Alkalinity is the capacity of bases to neutralize acids. An example is lime added to lakes to decrease acidity.

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The alkalinity is a measure of the negative ions that are available to react and neutralize free hydrogen ions. Some of most common of these include hydroxide (OH), sulfate (SO4), phosphate (PO4), bicarbonate (HCO3) and carbonate (CO3)

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An Alkalinity is Having the properties of a base with a pH of more than 7. A common Alkaline is baking soda.

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An alkalinity is the capacity of water for neutralizing an Acid solution.