Which of these reaction is correct ? — Redox Reactions and Volumetric Analysis Chemistry Question

💡 Solution & Explanation

Step 1: Identify the initial state of the reactants. Zinc hydroxide, Zn(OH)2↓, is an insoluble amphoteric white precipitate. Step 2: Observe the reaction with strong base. When excess sodium hydroxide (NaOH) is added, the precipitate reacts to form soluble sodium zincate (Na2ZnO2). Step 3: Because the insoluble precipitate dissolves to form a clear solution of a soluble complex salt, this is a precipitate dissolution reaction (type B). Thus, the correct option is (b).