Carbon's Superpower: Tetravalency & Catenation

Why it matters

Carbon can build an astonishing range of structures, from diamond to the carbon skeleton of DNA. It holds four hands and loves holding hands with itself.

Predict first

Why does carbon form millions of compounds while other elements form few?

Tetravalency lets carbon form four strong bonds, and catenation lets it link to itself in long chains and rings.

• Carbon is the most abundant element in the universe
• Carbon has tetravalency and catenation — correct
• Carbon is a non-metal
• Carbon has six valence electrons available for bonding

What you do

Carbon has four bonds to give, and it happily gives one to another carbon. Add carbons to grow a chain, then close it into a ring. Every carbon keeps all four bonds — that steady tetravalency, plus the endless self-linking called catenation, is what builds millions of compounds from diamond to DNA.

Check yourself

What is the valency of carbon in methane (CH₄)?

Carbon has 4 valence electrons and needs 4 more to complete its octet, so it forms 4 covalent bonds.

Which property allows carbon to form long chains?

Catenation is the unique ability of carbon atoms to form strong bonds with other carbon atoms, creating chains and rings.

Why doesn't silicon form as many compounds as carbon?

Although silicon is tetravalent, its larger size makes Si-Si bonds weaker and less stable than C-C bonds, limiting chain length.

• 2
• 4 — correct
• 1
• 3
• Catenation — correct
• Tetravalency
• Allotropy
• Isomerism
• Silicon is a metal
• Silicon-Silicon bonds are weaker than Carbon-Carbon bonds — correct
• Silicon has a different valency
• Silicon is too heavy