For acetone, CH3COCH3 Draw the Lewis structure and describe the hybridization of for each carbon atom in acetone Show σ and π bonds on the Lewis structure

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For acetone, CH3COCH3 Draw the Lewis structure and describe the hybridization of for each carbon atom in acetone Show σ and π bonds on the Lewis structure. How many σ and how many π bonds present in acetone? Draw a complete orbital overlap diagram showing all bonds, lone pairs, and bond angles. Identify each individual orbital and label the diagram with the σ and π bonds. Show the bond composition (which type of overlapping orbital) for all σ bonds.

The Correct Answer and Explanation is:

Here is the complete orbital overlap diagram for acetone (CH3COCH3):

mathematicaCopyEdit         H         H
          \       /
      (1s) H   H (1s)
            \   /
       sp3(C) — sp2(C) = sp2(O)
            /     \
      (1s) H   H (1s)
          /       \
         H         H

KEY OVERLAPS:
- C-H: sp3 (C) — 1s (H) → σ
- C-C: sp3 (methyl C) — sp2 (carbonyl C) → σ
- C=O σ: sp2 (C) — sp2 (O)
- C=O π: p (C) — p (O)

Explanation

Acetone contains three carbon atoms, one oxygen atom, and six hydrogen atoms. Each methyl carbon (CH3) is bonded to three hydrogen atoms and the carbonyl carbon. These methyl carbons are sp3 hybridized because they form four sigma bonds, which give them a tetrahedral geometry with bond angles of approximately 109.5 degrees. The overlapping orbitals for the C-H bonds involve an sp3 orbital from carbon and a 1s orbital from hydrogen, forming strong sigma bonds.

The central carbonyl carbon is sp2 hybridized, forming a trigonal planar structure with bond angles close to 120 degrees. This carbon makes three sigma bonds: two with the sp3 orbitals of the methyl carbons and one with an sp2 orbital of the oxygen atom. The sigma bond between the carbonyl carbon and the oxygen results from the overlap of their sp2 orbitals.

The remaining unhybridized p orbital on the carbonyl carbon overlaps sideways with an unhybridized p orbital on the oxygen atom. This sideways overlap forms the pi bond of the C=O double bond. Thus, the carbonyl bond consists of one sigma bond and one pi bond.

Overall, acetone has a total of nine sigma bonds and one pi bond. The sigma bonds provide the molecule with its strong framework, while the pi bond contributes to the double bond’s reactivity and partial polarity.

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