Reaction of Chloric Acid and Hydrochloric Acid to Form Paramagnetic Gas

To determine the product formed in the given sequence of reactions, let us analyze each step systematically:

Step 1: Reaction of Chloric Acid ($\text{HClO}_3$) with Hydrochloric Acid ($\text{HCl}$)

When chloric acid reacts with hydrochloric acid, a redox reaction occurs to yield chlorine dioxide gas ($\text{ClO}_2$), chlorine gas ($\text{Cl}_2$), and water: $2\text{HClO}_3(\text{aq}) + 2\text{HCl}(\text{aq}) \longrightarrow 2\text{ClO}_2(\text{g}) + \text{Cl}_2(\text{g}) + 2\text{H}_2\text{O}(\text{l})$

Step 2: Identification of the Paramagnetic Gas

• Chlorine dioxide ($\text{ClO}_2$): Total number of valence electrons = $7\,(\text{from Cl}) + 2 \times 6\,(\text{from O}) = 19$ valence electrons. Since it contains an odd number of electrons, $\text{ClO}_2$ is an odd-electron molecule and is paramagnetic.
• Chlorine ($\text{Cl}_2$): Has an even number of electrons and all electrons are paired, making it diamagnetic.

Hence, the paramagnetic gas produced is $\text{ClO}_2$.

Step 3: Reaction of the Paramagnetic Gas ($\text{ClO}_2$) with Ozone ($\text{O}_3$)

When chlorine dioxide reacts with ozone, it undergoes oxidation to form dichlorine hexoxide ($\text{Cl}_2\text{O}_6$): $2\text{ClO}_2 + 2\text{O}_3 \longrightarrow \text{Cl}_2\text{O}_6 + 2\text{O}_2$

Therefore, the product obtained upon subsequent reaction with $\text{O}_3$ is $\text{Cl}_2\text{O}_6$.

Correct Option: (C) $\text{Cl}_2\text{O}_6$