Which of the following combination of reagent(s) produce observable change in aqueous medium? — Redox Reactions and Volumetric Analysis Chemistry Question

💡 Solution & Explanation

Step 1: Identify the chemical properties of calcium oxalate (CaC2O4↓). It is an extremely insoluble salt in water. Step 2: Analyze the reaction with acetic acid. Acetic acid is a weak acid and does not provide a high enough concentration of hydronium ions to shift the solubility equilibrium of calcium oxalate (which only dissolves in strong mineral acids like HCl). Step 3: Since no chemical transformation or dissolution takes place, the reaction is classified as no reaction (type D). Thus, the correct option is (d).