Determine the values you need for pH
Use the formula pH = -log10[H+]
Find the hydrogen ion concentration [H+]
Substitute [H+] into the formula
Calculate the negative base-10 logarithm
If given pOH, use pH + pOH = 14
Solve for pH by subtracting pOH from 14
If given acid or base concentration, identify whether it is strong or weak
For strong acids, assume complete dissociation
For strong bases, calculate [OH-] from dissociation
Convert [OH-] to pOH using pOH = -log10[OH-]
Convert pOH to pH using pH = 14 – pOH
Check your units and significant figures
Report the final pH value