Question

The equation pH = -log 10C represents the ph of a substance, where C is the concentration, in milligrams per liter, of the chemical responsible for the level of acidity. If the pH of a lime is 2.4 and the pH of an orange is 4.0, what is the difference in acid concentration between the two fruits?

Answer 1

\[\text{pH} = -\log_{10}C\]
raising each sides of to exponents of 10
\[10^\text{pH} = 10^{-\log_{10}C}\]
simplifying
\[10^\text{pH} = 10^{\log_{10}\frac1C}\]\[10^\text{pH} = \frac1C\]\[C=\frac1{10^\text{pH}}\]\[C=10^\text{-pH}\]