The pH scale measures the concentration of hydrogen lons in acidic and alkaline solutions?

True.

Explanation:

The pH scale measures the concentration of hydrogen ions in acidic and alkaline solutions.

In chemistry, it literally means power of hydrogen ions and it is a measure of the molar concentration of hydrogen ions in a particular solution, thus specifying the acidity, neutrality or basicity of chemical solutions.

Mathematically, the pH of a solution is given by;

Hence, a solution with a pH of 7 is neutral. Also, a solution with a pH below 7 is acidic but basic (alkaline) if it's pH is above 7.

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