Covalent bonds are connections that form when atoms share electrons. There are three types of covalent bonds: single, double, and triple. The main differences between them are how many pairs of electrons they share and how strong they are.

1. Single Covalent Bonds

   • What It Is: Atoms share one pair of electrons.
   • Example: The bond between two hydrogen atoms (H-H) in hydrogen gas (H₂).
   • Strength: This bond is about 200-500 kJ/mol.
   • Length: It measures about 0.74 Å (angstroms).

2. Double Covalent Bonds

   • What It Is: Atoms share two pairs of electrons.
   • Example: The bond between two oxygen atoms (O=O) in oxygen gas (O₂).
   • Strength: This bond is stronger, about 400-800 kJ/mol.
   • Length: It is roughly 1.21 Å long.

3. Triple Covalent Bonds

   • What It Is: Atoms share three pairs of electrons.
   • Example: The bond between two nitrogen atoms (N≡N) in nitrogen gas (N₂).
   • Strength: This bond is the strongest, at about 800-1000 kJ/mol.
   • Length: It measures around 1.10 Å.

In Summary:

• Single bonds share 1 pair, double bonds share 2 pairs, and triple bonds share 3 pairs.
• The strength of the bonds increases as you go from single to triple.
• The length of the bonds gets shorter from single to triple bonds.