Common Ion Effect and pH Calculation for Buffer Solutions (using weak acid and its salt as an example)
Formula: pH = pK a + lg ([salt])/([acid]) (Henderson - Hasselbalch equation). Applicable conditions: Buffer solutions (composed of a weak acid and its conjugat…
Syllabus path: Chemical Theories and Laws › Electrolyte Solution Theory
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CSCA Chemistry Formula Reference
Formula and explanation
Formula: pH = pK a + lg ([salt])/([acid]) (Henderson - Hasselbalch equation). Applicable conditions: Buffer solutions (composed of a weak acid and its conjugate base or a weak base and its conjugate acid), works best when the concentration ratio is between 0.1 and 10. Description: This formula is used to calculate the pH of a buffer solution. Adding a strong electrolyte containing a common ion (common ion effect) suppresses the ionization of the weak electrolyte. A buffer solution resists changes in pH upon addition of small amounts of acid, base, or dilution.
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Electrolyte Solution Theory
Electrolyte Solution Theory Core Concepts and Learning Objectives This section focuses on chemical reactions in aqueous solutions, centering on the behavior of ions (Ionization, Hydrolysis, Precipitation). This is a high - frequency topic for calculation questions (pH, Ksp) and l…
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