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

Answer: (C)

1

Answer 2

Among the given species. $\text{S}_2\text{O}_3^{2-}$ (thiosulfate ion) has a pyramidal geometry around the central sulfur atom due to the presence of a lone pair on sulfur, resulting in a trigonal pyramidal shape.$\text{SO}_4^{2-}$ (sulfate ion) has a tetrahedral geometry due to its symmetrical distribution of oxygen atoms around the central sulfur atom.$\text{SO}_3^{2-}$ (sulfite ion) also adopts a trigonal pyramidal structure around sulfur, but in this context, $\text{S}_2\text{O}_3^{2-}$ is more relevant to pyramidal geometry.$\text{S}_2\text{O}_7^{2-}$ (disulfate ion) has a tetrahedral arrangement with respect to its central atoms, making it non-pyramidal.
Therefore, only one species, $\text{S}_2\text{O}_3^{2-}$, exhibits pyramidal geometry.