If you know pH, it’s easy to calculate pOH because pH + pOH = 14. Sometimes you need to calculate pOH from the hydroxide ion concentration [OH-]. You’ll need a calculator here, using the equation pOH = -log[OH-].
What is a pOH value?
The pOH of an aqueous solution is the negative logarithm of the hydroxide ion (OH–) concentration. pOH = -log[OH – ] As with pH, pOH values range from 1 to 14, where 7 is neutral. The scales for pH and pOH are opposites of one another.
Why does pH plus pOH equal 14?
The sum of pH and pOH is always 14. This is because the product of proton concentration and hydroxide concentration must always equal the equilibrium constant for the ionization of water, which is equal to . In this question, we know that the pOH is equal to 2.13, allowing us to solve for the pH.
How do you get pOH from OH?
The hydroxide ion concentration can be found from the pOH by the reverse mathematical operation employed to find the pOH. [OH-] = 10-pOH or [OH-] = antilog ( – pOH) Page 2 Example: What is the hydroxide ion concentration in a solution that has a pOH of 5.70? On a calculator calculate 10-5.70, or “inverse” log (- 5.70).
What is the equation that relates to pH and pOH?
Use the pOH equation pH=−log[OH−] and pKw equation pKw=pH+pOH=14 .
What does pOH mean in chemistry?
pOH is a measure of the hydroxide ion (OH-) concentration of a solution. As such, it can be used as an indicator of a substance’s alkalinity or even its electrical conductivity in some cases. More specifically, pOH is the negative logarithm of the hydroxide ion content given by the expression: pOH = 14 – pH.
What is pOH of a solution?
The pOH of a solution is the negative logarithm of the hydroxide-ion concentration: pOH=−log[OH−] The pH of a solution can be related to the pOH.
What is the pOH of water?
In the case of pure water, there are always the same concentration of hydrogen ions and hydroxide ions and hence, the water is still neutral (pH = pOH) – even if its pH changes. The problem is that we are all familiar with 7 being the pH of pure water, that anything else feels really strange.
What does high pOH mean?
pH and pOH denote the negative log of the concentration of hydrogen or hydroxide ions. High pH means that a solution is basic while high pOH means that a solution is acidic.
How do you find the pOH of HCl?
Key Concepts
The pOH of an aqueous solution of a strong monoprotic acid can be calculated if we know: (i) the concentration of hydroxide ions in solution. or. For an acidic solution: pOH = -log10[OH-] For an aqueous acidic solution at 25°C pOH = 14 – pH. For an aqueous acidic solution at 25°C pOH = 14 – (-log10[H+(aq)])
