Identify the solution type: strong acid, strong base, weak acid, weak base, buffer, or salt
Determine the concentration of the relevant hydrogen ion or hydroxide ion
For strong acids, use pH = -log[H+]
For strong bases, use pOH = -log[OH-]
Convert pOH to pH using pH + pOH = 14
For weak acids, use the acid dissociation constant Ka and an ICE table
For weak bases, use the base dissociation constant Kb and an ICE table
Use pH = -log[H+] after finding [H+]
Use pOH = -log[OH-] after finding [OH-]
For buffers, use the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA])
For salt solutions, determine whether the ions hydrolyze in water
For polyprotic acids, calculate pH using the first dissociation if it dominates
For very dilute solutions, account for water autoionization if needed
Check significant figures in the final pH value
Verify whether the result should be acidic, neutral, or basic