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High-Tech Channel Hitachi High-Tech GLOBAL

What does the “7” in “pH7” represent?

Symbol: pH, PH / Base data: Density.
Unit that expresses density of hydrogen ion [H+]. Shown as common logarithm of the reciprocal of hydrogen ion

Expresses density of hydrogen ion

pH is a relatively familiar unit that expresses the acidity and alkalinity of things such as cosmetics, food, and hot water springs. However, what do the numbers represent? They express the density of hydrogen ion in a solution. When hydrogen ion increases and hydroxyl ion decreases, the solution becomes acidic.