Question

Which of the following compound have ${\text{X}} - {\text{O}} - {\text{X}}$ linkage where ‘${\text{X}}$’ is the so called central atom like ${\text{P}}$, ${\text{S}}$ etc?
(A) ${{\text{P}}_{\text{2}}}{\text{O}}_8^{4 - }$
(B) ${{\text{S}}_{\text{2}}}{\text{O}}_3^{2 - }$
(C) $\gamma - {\text{S}}{{\text{O}}_3}$
(D) ${{\text{S}}_{\text{2}}}{\text{O}}_5^{2 - }$

Answer 1

To solve this we must first draw the structures of all the four given compounds. From the structures we can determine the compound having ${\text{X}} - {\text{O}} - {\text{X}}$ linkage. First of all we should draw the exact structure of the compound to find out the central atom.

Complete Step by step answer: ${{\text{P}}_{\text{2}}}{\text{O}}_8^{4 - }$ is known as peroxydisulfate ion. Draw the structure of ${{\text{P}}_{\text{2}}}{\text{O}}_8^{4 - }$:

In the structure of ${{\text{P}}_{\text{2}}}{\text{O}}_8^{4 - }$, we cannot see ${\text{P}} - {\text{O}} - {\text{P}}$ linkage. Thus, ${{\text{P}}_{\text{2}}}{\text{O}}_8^{4 - }$ does not have ${\text{X}} - {\text{O}} - {\text{X}}$ linkage.
Thus, option (A) is not correct.
${{\text{S}}_{\text{2}}}{\text{O}}_3^{2 - }$ is known as thiosulphate ion. Draw the structure of ${{\text{S}}_{\text{2}}}{\text{O}}_3^{2 - }$:

In the structure of ${{\text{S}}_{\text{2}}}{\text{O}}_3^{2 - }$, we cannot see ${\text{S}} - {\text{O}} - {\text{S}}$ linkage. Thus, ${{\text{S}}_{\text{2}}}{\text{O}}_3^{2 - }$ does not have ${\text{X}} - {\text{O}} - {\text{X}}$ linkage.
Thus, option (B) is not correct.
$\gamma - {\text{S}}{{\text{O}}_3}$ is known as sulphur trioxide. Draw the structure of $\gamma - {\text{S}}{{\text{O}}_3}$:

In the structure of $\gamma - {\text{S}}{{\text{O}}_3}$, we can see ${\text{S}} - {\text{O}} - {\text{S}}$ linkage. The ${\text{S}} - {\text{O}} - {\text{S}}$ is shown in red colour. Thus, $\gamma - {\text{S}}{{\text{O}}_3}$ has ${\text{X}} - {\text{O}} - {\text{X}}$ linkage.
Thus, option (C) is correct.
${{\text{S}}_{\text{2}}}{\text{O}}_5^{2 - }$ is known as metabisulphite. Draw the structure of ${{\text{S}}_{\text{2}}}{\text{O}}_5^{2 - }$:

In the structure of ${{\text{S}}_{\text{2}}}{\text{O}}_5^{2 - }$, we cannot see ${\text{S}} - {\text{O}} - {\text{S}}$ linkage. Thus, ${{\text{S}}_{\text{2}}}{\text{O}}_5^{2 - }$ does not have ${\text{X}} - {\text{O}} - {\text{X}}$ linkage.
Thus, option (D) is not correct.
Thus, the compound have ${\text{X}} - {\text{O}} - {\text{X}}$ linkage where ‘${\text{X}}$’ is the so called central atom like ${\text{P}}$, ${\text{S}}$ etc is $\gamma - {\text{S}}{{\text{O}}_3}$.

Thus, the correct option is (C) $\gamma - {\text{S}}{{\text{O}}_3}$.

Note: Sulphur trioxide $\left( {{\text{S}}{{\text{O}}_3}} \right)$ has many structural changes and thus, it has many different forms. These changes are caused by the traces of water. $\gamma - {\text{S}}{{\text{O}}_3}$ is very pure gaseous sulphur trioxide. It is a trimeric structure i.e. it has three molecules of sulphur trioxide. $\gamma - {\text{S}}{{\text{O}}_3}$ forms a cyclic structure. It is colourless solid in appearance. Sulphur trioxide is highly hygroscopic in nature i.e. it can easily attract water molecules from its surroundings by absorption or adsorption.