H valence electrons: 1 C valence electrons: 4 O valence electrons: 6

Question

Based on this information, how many single and how many double bonds are found in carbonic acid?

Answer 1

Carbonic acid (H₂CO₃) has the following structure:

1. The central atom is carbon (C), which is bonded to two hydroxyl groups (–OH) and one carbonyl group (C=O).
2. Carbon has 4 valence electrons and typically forms 4 bonds.
3. Oxygen (O) has 6 valence electrons and typically forms 2 bonds, either as single bonds (–O–) or double bonds (C=O).
4. Hydrogen (H) has 1 valence electron and forms 1 bond.

In carbonic acid, the bonding can be summarized as follows:

• The carbon atom forms:
  • 1 double bond with one oxygen atom (C=O)
  • 1 single bond with another oxygen atom that is part of a hydroxyl group (–OH)
  • 1 single bond with the other hydroxyl group (–OH)

Thus, in carbonic acid, there is:

• 1 double bond (C=O).
• 2 single bonds (C–O in each hydroxyl group).

To conclude:

• Carbonic acid contains 1 double bond and 2 single bonds.