Problem 134 - A Complete Resource Book in Chemistry for JEE Main

Question

Which are the species in which sulphur undergoes \(\mathrm{sp}^{3}\) hybridization? (1) SF \(_{4}\) (2) \(\mathrm{SCl}_{2}\) (3) \(\mathrm{SO}_{4}^{2-}\) (4) \(\mathrm{H}_{2} \mathrm{~S}\) Select the correct answer using the code given below: (a) 1 and 2 (b) 2,3 and 4 (c) 1,3 and 4 (d) 1,2 and 3

Step-by-Step Solution

Answer

The correct species are SCl₂, SO₄²⁻, and H₂S. Answer: (b) 2, 3, and 4.

Step 1: Understanding sp³ Hybridization

sp³ hybridization occurs when one s orbital and three p orbitals mix to form four equivalent hybrid orbitals, each oriented towards the corners of a tetrahedron. For sulphur, sp³ hybridization results in four bonds or lone pairs around it.

Step 2: Analyzing Each Compound

Let's analyze each given compound to determine if sulfur undergoes sp³ hybridization: 1. **SF₄**: Sulphur forms four bonds with fluorine atoms and has one lone pair, totaling 5 electron pairs. This is actually an example of sp³d hybridization. 2. **SCl₂**: Sulfur forms two bonds with chlorine atoms and has two lone pairs, totaling 4 electron pairs, fitting sp³ hybridization. 3. **SO₄²⁻**: Sulfur forms four double bonds with oxygen atoms, which form resonance structures, typically associated with sp³ hybridization. 4. **H₂S**: Sulfur forms two bonds with hydrogen atoms and has two lone pairs, totaling 4 electron pairs, fitting sp³ hybridization.

Step 3: Selecting the Correct Answer

Given that SCl₂ (2), SO₄²⁻ (3), and H₂S (4) all show sp³ hybridization, the correct choice includes these compounds. Thus, the correct answer is option (b) 2, 3, and 4.

Key Concepts

Sulfur Compounds

Sulfur is a fascinating element, known for its versatility in forming various compounds. It can bond with a range of other elements, resulting in unique substances like sulfur dioxide (SO₂) and hydrogen sulfide (H₂S). These compounds significantly vary in their physical and chemical properties. For example:

• Sulfur Dioxide (SO₂): It's a toxic gas with a characteristic smell, widely used in industrial processes and as a preservative.
• Hydrogen Sulfide (H₂S): Known for its rotten egg smell, this compound is produced naturally in volcanic gases and during the decay of organic matter.
• Sulfur Hexafluoride (SF₆): An effective electrical insulator, this compound is used in the power industry.

These variations are due to sulfur's ability to adopt different oxidation states and hybridizations, such as sp³, which influences its role in chemical bonding and molecular geometry.

Chemical Bonding

Chemical bonding centers on how atoms connect to form stable molecules. Understanding the type of bonds formed by sulfur is crucial for chemistry enthusiasts. Sulfur can participate in several types of chemical bonds, such as:

• Covalent Bonds: Sulfur often shares electrons with other atoms to form strong covalent bonds, as seen in SF₆ and H₂S.
• Double Bonds: In sulfate ions (SO₄²⁻), sulfur forms double bonds with oxygen, contributing to resonance structures and stability.

The concept of hybridization helps explain the bond angles and molecular shapes in sulfur compounds. In sp³ hybridization, sulfur's electron configuration changes, allowing it to form four tetrahedrally oriented orbitals. This results in a balanced distribution of electrons across the molecule, influencing both the reactivity and properties of the compound.

Molecular Geometry

Molecular geometry describes the three-dimensional arrangement of atoms in a molecule. It's essential to predict the molecule's shape as it influences its physical and chemical properties significantly. In sulfur compounds:

• SCl₂: Sulfur exhibits a bent shape due to sp³ hybridization with two lone pairs, which leads to a bond angle of about 103°.
• SO₄²⁻: Here, sulfur’s geometry is tetrahedral, resulting in symmetrical bonds and influence from resonance, which stabilizes the structure.
• H₂S: This compound shares similar geometry with water, forming a bent shape, due to the sp³ hybridization and its lone pairs.

The determination of molecular geometry helps in understanding various properties like polarity, reactivity, and interaction with other molecules, which are critical for assessing how these compounds interact in real-world applications.