The number of species from the following that have pyramidal geometry around the central atom is ______
\( \text{S}_2\text{O}_3^{2-}, \, \text{SO}_4^{2-}, \, \text{SO}_3^{2-}, \, \text{S}_2\text{O}_7^{2-} \)
\( \text{S}_2\text{O}_3^{2-}, \, \text{SO}_4^{2-}, \, \text{SO}_3^{2-}, \, \text{S}_2\text{O}_7^{2-} \)
- 4
- 3
- 1
- 2
The Correct Option is C
Approach Solution - 1
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.
Approach Solution -2
We are asked to find how many among the given species have pyramidal geometry around the central atom. Pyramidal geometry (like in NH₃) arises when the central atom has three bonding pairs and one lone pair of electrons (sp³ hybridization with one lone pair).
The species are:
1. \( \text{S}_2\text{O}_3^{2-} \) (thiosulfate ion)
2. \( \text{SO}_4^{2-} \) (sulfate ion)
3. \( \text{SO}_3^{2-} \) (sulfite ion)
4. \( \text{S}_2\text{O}_7^{2-} \) (pyrosulfate ion)
Step 2: Analyze each species
(1) Thiosulfate ion, \( \text{S}_2\text{O}_3^{2-} \)
- Structure: one central sulfur atom bonded to three oxygen atoms (one double-bonded, two single-bonded) and one terminal sulfur atom.
- Central sulfur has 4 regions of electron density (3 S–O bonds + 1 S–S bond).
- All are bonding pairs, no lone pairs → geometry is tetrahedral.
(2) Sulfate ion, \( \text{SO}_4^{2-} \)
- Structure: sulfur atom surrounded by four oxygen atoms through sigma bonds (sp³ hybridized).
- No lone pairs on sulfur → geometry is tetrahedral.
(3) Sulfite ion, \( \text{SO}_3^{2-} \)
- Structure: sulfur atom bonded to three oxygen atoms and has one lone pair of electrons (sp³ hybridization).
- 3 bond pairs + 1 lone pair → geometry is pyramidal.
(4) Pyrosulfate ion, \( \text{S}_2\text{O}_7^{2-} \)
- Structure: two tetrahedral \(\text{SO}_4\) units joined by one oxygen bridge.
- Each sulfur atom is tetrahedrally surrounded (no lone pairs).
- Geometry around each sulfur → tetrahedral.
Step 3: Conclusion
Only \( \text{SO}_3^{2-} \) (sulfite ion) has a pyramidal geometry due to the presence of one lone pair on sulfur.
Final answer
Top JEE Main Chemistry Questions
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- At equilibrium the concentrations of and in a sealed vessel at . What will be for the reaction
- Find out the major products from the following reactions
Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
- The correct order of atomic radii is:
Top JEE Main The Valence Shell Electron Pair Repulsion (VSEPR) Theory Questions
Top JEE Main Questions
- Two masses $m$ and $\frac{m}{2}$ are connected at the two ends of a massless rigid rod of length $l$. The rod is suspended by a thin wire of torsional constant $k$ at the centre of mass of the rod-mass system(see figure). Because of torsional constant $k$, the restoring torque is $\tau =k\theta$ for angular displacement $\theta$. If the rod is rota ted by $\theta_0$ and released, the tension in it when it passes through its mean position will be:
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- The value of is
- The number of terms of an is even. The sum of the odd terms is and of the even terms is . The last term exceeds the first by . Then the number of terms in the series is ______.
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,