If d_x^2-y^2 and p_y-orbital come close together along z-axis, then they can form \pi-bond by sidewa — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Determine the number of π-bonds in each thionic/sulfur oxyacid species by drawing their Lewis structures to satisfy octets/valencies (S exhibits variable valency up to 6). Step 2: Calculate the π-bonds: (II) H2S2O3 has 2 π-bonds; (III) H2S2O5 has 3 π-bonds; (I) H2S2O6 has 4 π-bonds. Step 3: Order the compounds by increasing number of π-bonds: II (2) < III (3) < I (4), which corresponds to option (c).