Which statement correctly describes why the pH scale is logarithmic?

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The pH scale is logarithmic because pH is calculated using the formula $	ext{pH} = -\log_{10}[	ext{H}^+]$. This logarithmic relationship means that when the hydrogen ion concentration decreases by a factor of 10, the pH increases by exactly 1 unit. For example, if the concentration changes from $10^{-3}$ mol/L (pH 3) to $10^{-4}$ mol/L (pH 4), we see a tenfold decrease in $[	ext{H}^+]$ paired with a one-unit increase in pH. This non-linear behaviour is the defining characteristic of a logarithmic scale and allows us to express a very wide range of hydrogen ion concentrations (from $10^0$ to $10^{-14}$ mol/L) using a compact pH scale of 0 to 14.

Identify that the pH scale is a logarithmic scale.

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