Question

The number of species from the following that have pyramidal geometry around the central atom is ______
\( \text{S}_2\text{O}_3^{2-}, \, \text{SO}_4^{2-}, \, \text{SO}_3^{2-}, \, \text{S}_2\text{O}_7^{2-} \)

• A. 4
• B. 3
• C. 1
• D. 2

Answer 1

The Correct Option is C

Of the species provided, \( \text{S}_2\text{O}_3^{2-} \) (thiosulfate ion) displays a pyramidal geometry around the central sulfur atom, attributed to a lone pair on sulfur, leading to a trigonal pyramidal shape. \( \text{SO}_4^{2-} \) (sulfate ion) exhibits tetrahedral geometry due to the symmetrical arrangement of oxygen atoms around the central sulfur atom. \( \text{SO}_3^{2-} \) (sulfite ion) also adopts a trigonal pyramidal structure around sulfur; however, in this context, \( \text{S}_2\text{O}_3^{2-} \) is more pertinent to pyramidal geometry. \( \text{S}_2\text{O}_7^{2-} \) (disulfate ion) possesses a tetrahedral arrangement concerning its central atoms, rendering it non-pyramidal.
Consequently, only \( \text{S}_2\text{O}_3^{2-} \) demonstrates pyramidal geometry.