# How many times more basic is a pH of 12 compared to a pH of 8?

Oct 8, 2016

10000 times more basic

#### Explanation:

Since pH is a logarithmic scale, a change in pH of 1 results in a ten-fold change in the concentration of ${H}^{+}$, which would be a ten-fold change in acidity/basicity . This is because how acidic/basic a substance is can be determined by the concentration of hydrogen ions. The more ${H}^{+}$ ions present, the more acidic the substance is, due to the fact that acids donate ${H}^{+}$ ions. On the other hand, bases accept ${H}^{+}$ ions, and thus the lower the concentration of ${H}^{+}$, the more basic the substance is.

You can calculate the concentration of ${H}^{+}$ from the pH and the equation $p H = - \log \left[{H}^{+}\right]$. Rearranging, we get $\left[{H}^{+}\right] = {10}^{- p H}$

So for a pH of 8, we get $\left[{H}^{+}\right] = {10}^{-} 8$
For a pH of 12, we get $\left[{H}^{+}\right] = {10}^{-} 12$

${10}^{-} \frac{8}{10} ^ - 12 = {10}^{4} = 10000$ times less ${H}^{+}$ ions and thus $10000$ times more basic