Definition of pH
pH is defined as the negative common logarithm of the hydrogen ion activity a(H⁺). In dilute solutions, the hydrogen ion concentration [H⁺] is often used as an…
Syllabus path: Fundamental Chemical Concepts and Calculations › Solution Concentration and pH Calculations
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CSCA Chemistry Formula Reference
Formula and explanation
pH is defined as the negative common logarithm of the hydrogen ion activity a(H⁺). In dilute solutions, the hydrogen ion concentration [H⁺] is often used as an approximation for activity. Formula: pH = - lg a(H⁺) ≈ - lg [H⁺] Applicable conditions: Applies to aqueous solutions. For dilute solutions (typically concentration < 0.1 mol/L), using concentration is a reasonable approximation. Brief description: pH is a key indicator of the acidity or basicity of a solution. pH < 7 is acidic, pH = 7 is neutral, pH > 7 is basic.
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Solution Concentration and pH Calculations
Core Concepts: Solution Concentration and pH Calculations This section is not only a major area for calculation problems but also the foundation for lab questions (Solution Preparation). In the CSCA exam, the conversion between Molarity and Mass Percentage and pH of Mixtures are …
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