Which of the following reagents can be used to distinguish between SO2 and CO2? — Qualitative and Quantitative Analysis Chemistry Question

💡 Solution & Explanation

Step 1: Chromium(VI) is a strong oxidizing agent, and bromide ion (Br-) is a moderate reducing agent. Step 2: Chromyl chloride (CrO2Cl2) is stable and well-known. However, the analogous chromyl bromide (CrO2Br2) is highly unstable because of the ready oxidation of bromide by Cr(VI) to form bromine gas (Br2) and Cr(III). Step 3: Therefore, chromyl bromide (CrO2Br2) does not exist under ordinary conditions, making option (a) the correct choice.