Draw the Lewis structure for H2SO4

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Draw the Lewis structure for H2SO4, a neutral molecule.

The correct answer and explanation is :

The Lewis structure of sulfuric acid (H₂SO₄) consists of a central sulfur atom bonded to four oxygen atoms, with two of those oxygens also bonded to hydrogen atoms. Below is the correct Lewis structure:

Step-by-Step Construction:

  1. Determine the Total Valence Electrons:
  • Hydrogen (H) = 1 × 2 = 2
  • Sulfur (S) = 6 × 1 = 6
  • Oxygen (O) = 6 × 4 = 24
  • Total Valence Electrons = 2 + 6 + 24 = 32 electrons
  1. Identify the Central Atom:
  • Sulfur (S) is the least electronegative (except hydrogen) and can expand its octet.
  1. Draw Single Bonds:
  • Connect sulfur to four oxygens via single bonds.
  • Attach hydrogens to two oxygens, making hydroxyl (-OH) groups.
  1. Complete the Octets:
  • The two OH oxygens have 8 electrons (2 from bonding, 6 as lone pairs).
  • The remaining two oxygens form double bonds with sulfur to satisfy the octet rule.
  1. Check Formal Charges:
  • The double-bonded oxygens have a formal charge of 0.
  • The OH groups keep neutral charges.
  • Sulfur follows the expanded octet rule (12 valence electrons) but remains neutral.

Final Structure:

    O
    ||
H—O—S—O—H
    ||
    O

The molecule is tetrahedral around sulfur, and resonance occurs in the double-bonded oxygens.

Explanation:

  • Strong Acid Properties: H₂SO₄ is a strong acid because the O-H bonds readily dissociate in water.
  • Octet Expansion: Sulfur can hold more than 8 electrons due to its position in Period 3.
  • Resonance: The two S=O bonds resonate, making the structure more stable.

This structure correctly follows valence and charge rules, explaining H₂SO₄’s strong acidity and molecular stability.

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