Draw the lewis structures of SO3Na and H3CO
The Correct Answer and Explanation is :
To understand the Lewis structures of SO₃Na and H₃CO, let’s break them down:
1. SO₃Na (Sodium Sulfite)
- Atoms involved: Sodium (Na), Sulfur (S), and Oxygen (O).
- Step 1: Identify the central atom.
Sulfur is the central atom as it is less electronegative than oxygen and can form multiple bonds. - Step 2: Count valence electrons.
- Sodium (Na): 1 valence electron.
- Sulfur (S): 6 valence electrons.
- Oxygen (O): 6 valence electrons (3 oxygens in total). Total valence electrons: 1 (Na) + 6 (S) + 3×6 (O) = 25 valence electrons.
- Step 3: Bonding.
Sodium (Na) will lose its one valence electron, forming a Na⁺ ion. This leaves behind the sulfate ion (SO₃²⁻), where sulfur is double-bonded to each oxygen atom. - Step 4: Assign electron pairs.
- Sulfur (S) will form 3 double bonds with the three oxygen atoms. This uses up 6 electrons.
- Each oxygen will have 2 lone pairs, each using up 2 electrons (3×2 = 6).
- This structure leaves 2 extra electrons that will be placed on sulfur to complete its octet.
The Lewis structure of SO₃Na shows sulfur double-bonded to three oxygens with one oxygen forming an ionic bond with sodium. The sulfur atom has a formal charge of 0, and each oxygen has a formal charge of -1.
2. H₃CO (Formyl Group)
- Atoms involved: Hydrogen (H), Carbon (C), and Oxygen (O).
- Step 1: Identify the central atom.
Carbon is the central atom as it is less electronegative than oxygen. - Step 2: Count valence electrons.
- Hydrogen (H): 1 valence electron (3 hydrogens = 3).
- Carbon (C): 4 valence electrons.
- Oxygen (O): 6 valence electrons. Total valence electrons: 3 (H) + 4 (C) + 6 (O) = 13 valence electrons.
- Step 3: Bonding.
Carbon will be bonded to 3 hydrogens and double-bonded to oxygen. - Step 4: Assign electron pairs.
- Carbon (C) will have 3 single bonds with hydrogen and 1 double bond with oxygen.
- Oxygen will have 2 lone pairs.
The Lewis structure of H₃CO shows carbon bonded to three hydrogen atoms and double-bonded to oxygen. The oxygen atom has 2 lone pairs.
Conclusion:
- SO₃Na: Sulfur is double-bonded to three oxygens, with one oxygen ionically bonded to sodium.
- H₃CO: Carbon is single-bonded to three hydrogens and double-bonded to oxygen.