Which one of the following statements is NOT correct?

The pH of a solution is defined as the negative logarithm to the base $10$ of the hydrogen ion concentration, expressed as $pH = -\log_{10}[H^+]$.

Because of the negative sign in the formula, an increase in the hydrogen ion concentration $[H^+]$ results in a decrease in the pH value. Therefore, the higher the hydrogen ion concentration in a solution, the lower is its pH.

The other statements are correct: the pH scale measures hydrogen ion concentration, it generally ranges from $0$ to $14$, and the 'p' stands for 'potenz' (meaning power) in German.

Answer: The higher the hydrogen ion concentration in a solution, higher is its pH