Question

Calculate the pH and pOH of the solutions with the following hydrogen ion or hydroxide ion concentrations. Indicate which solutions are acidic, basic, or neutral. [OH–] = 9.21×10^-9 M______ pH______ pOH

Answer 1

Answer

pOH=8.036

pH=5.964

The solution is acid

Procedure

We need to consider the following when we speak about pH and pOH

As we have a concentration of [OH-] ions, we will first calculate the pOH

$pOH=-log[9.21\times10^{-9}]=8.0357$

Then we calculate the pH assuming the solution is at 25 C.

$pH=14-pOH=5.9642$

We can see that as the pH of this solution is lower than 7, the solution will be acid.