Which of the following statement(s) is/are correct when a solid mixture of NaCl and K2Cr2O7 is gentl β Qualitative and Quantitative Analysis Chemistry Question
Question
Which of the following statement(s) is/are correct when a solid mixture of NaCl and K2Cr2O7 is gently warmed with conc. H2SO4 ?
π‘ 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).