Which of the following statements rigorously describe the variation in equivalent weights of primary — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question

💡 Solution & Explanation

Step 1: Evaluate $KMnO_4$. In acidic medium, $Mn^{+7} \rightarrow Mn^{+2}$ (change of 5 $\Rightarrow$ E = M/5). In neutral/weakly alkaline medium, $Mn^{+7} \rightarrow Mn^{+4}$ (change of 3 $\Rightarrow$ E = M/3). In strongly alkaline medium, $Mn^{+7} \rightarrow Mn^{+6}$ (change of 1 $\Rightarrow$ E = M/1). Options A, C, and D are correct. Step 2: Evaluate $K_2Cr_2O_7$. In acidic medium, $Cr_2O_7^{2-} \rightarrow 2Cr^{3+}$. The oxidation state of each Cr changes from +6 to +3. Since there are 2 Cr atoms, total change = $2 \times 3 = 6$ (n-factor = 6 $\Rightarrow$ E = M/6). Option B is correct.