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pH scale is a system of describing acidity or alkalinity, ranging from pH 0 to pH 14, with pH 7 being neutral. Values lower than 7 indicate acidity; those higher than 7 indicate alkalinity. Each number on the pH scale represents a tenfold change in acidity or alkalinity. Thus pH 5 is 10 times more acid than pH 6, and pH 4 is 100 times more acid than pH 6; pH 11 is 1,000 times more alkaline than pH 8. In general, plants grow best in the pH range of 4 (very acid) to 8 (slightly alkaline). (Source: Wikipedia)
Alkalosis refers to a condition reducing hydrogen ion concentration of arterial blood plasma (alkalemia). Generally alkalosis is said to occur when arterial pH exceeds 7.45. The opposite condition is acidosis. (Source: Wikipedia)
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