Algebra
# Exponential Functions

\(pH\) measures the concentration of hydrogen ions \(H^+\) in a solution. Let \(pH=m\) if the number of gram ions of \(H^+\) in a \(1\)-liter solution is \(10^{-m}\).

Then the ratio of the number of gram ions of \(H^+\) for \(pH=6.5\) and the number of gram ions of \(H^+\) for \(pH=7.9\) can be expressed as \(10^a.\) What is the value of \(100a?\)