Draw the Lewis structure for Calcium Carbonate

Draw the Lewis structure for Calcium Carbonate (CaCO3

The correct answer and explanation is:

Lewis Structure of Calcium Carbonate (CaCO₃)

Calcium carbonate (CaCO₃) consists of calcium ions (Ca²⁺) and carbonate ions (CO₃²⁻). Since calcium is a metal, it donates electrons to form a Ca²⁺ ion, and carbonate is a polyatomic ion with covalent bonds between carbon and oxygen.


Steps to Draw the Lewis Structure of CO₃²⁻

  1. Determine the total valence electrons:
    • Carbon (C) has 4 valence electrons.
    • Oxygen (O) has 6 valence electrons (3 oxygen atoms = 18 electrons).
    • The extra 2 negative charges contribute 2 more electrons.
    • Total = 4 + 18 + 2 = 24 valence electrons.
  2. Sketch the basic structure:
    • Carbon is the central atom.
    • Three oxygens surround the carbon.
  3. Assign single bonds first:
    • Draw single bonds between C and O, using 6 electrons (3 bonds × 2 electrons).
  4. Distribute remaining electrons:
    • 24 – 6 = 18 electrons left.
    • Distribute these on oxygen atoms to satisfy the octet rule.
  5. Check for octets and formal charges:
    • Carbon lacks a full octet, so form a double bond with one oxygen.
    • This results in one C=O bond and two C–O⁻ single bonds, where the negative charges reside on the two singly bonded oxygens.

Final Structure

  • Calcium (Ca²⁺) does not participate in covalent bonding; it simply balances the charge.
  • The final structure consists of:
    • A carbonate ion (CO₃²⁻) with resonance between the oxygen atoms.
    • A Ca²⁺ ion that interacts electrostatically.

Now, I will generate the image of the Lewis structure.

Here is the Lewis structure diagram for Calcium Carbonate (CaCO₃). Let me know if you need any modifications or further explanations!

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