MgCO3 is not precipitated with the carbonates of Vth group radicals in presence of NH4Cl and NH4OH b — Qualitative and Quantitative Analysis Chemistry Question

💡 Solution & Explanation

Step 1: Ammonium chloride (NH4Cl) is a strong electrolyte that dissociates completely to provide a high concentration of NH4+ ions. Step 2: The high concentration of NH4+ suppresses the dissociation of (NH4)2CO3 through the common ion effect, keeping the carbonate ion (CO3^2-) concentration low. Step 3: This low concentration of CO3^2- is sufficient to exceed the solubility products of Group V carbonates (BaCO3, SrCO3, CaCO3) but is too low to precipitate MgCO3. Therefore, MgCO3 is not precipitated in the presence of NH4Cl, matching option (b).