If pH 7 is neutral, how many times more alkaline is a pH of 9?

A pH scale is logarithmic, which means that each whole number change represents a tenfold change in acidity or alkalinity. At a pH of 7, the solution is neutral. As you move up the scale to pH 9, the solution becomes more alkaline.

To determine how many times more alkaline pH 9 is compared to pH 7, you can calculate the difference in pH level:

• The difference between 9 and 7 is 2.

• Since each unit change in pH represents a tenfold increase or decrease, pH 9 is 10 raised to the power of 2 (10^2).

This results in a factor of 100. Thus, a solution with a pH of 9 is 100 times more alkaline than a solution with a pH of 7. Understanding this logarithmic relationship is essential in areas such as skincare, as it influences product formulations and their effectiveness based on the pH levels.