Small size gives strong carbon bonds

The idea

Carbon's small size lets its nucleus hold shared electron pairs strongly, so its bonds with most elements are very strong and its compounds exceptionally stable; elements with bigger atoms form much weaker bonds.

Small and strong

Carbon atoms are small. Elements with bigger atoms are different.

Think of an atom holding on to the pair of electrons it shares with a neighbour. How does a small atom compare with a bigger atom?

• A bigger atom holds the shared pair more strongly
• A small atom holds the shared pair more strongly
• Size makes no difference to the hold

Small versus big

Open every tab.

Why small is strong

In these pictures the small atom's nucleus is closer to the shared pair. The book says a small size lets the nucleus hold the pair strongly.

Carbon's small size lets its nucleus hold the shared electron pairs strongly, so its bonds with most elements are very strong and its compounds exceptionally stable. Elements with bigger atoms form much weaker bonds.

Notes

Carbon's small size lets its nucleus hold shared pairs strongly, so its bonds with most elements are very strong and its compounds exceptionally stable. Elements with bigger atoms form much weaker bonds.

Check yourself

Why does carbon form strong bonds?

How are the bonds formed by elements with bigger atoms?

What does the strength of carbon's bonds give its compounds?

Which atom's nucleus holds a shared pair more strongly?

• Its small size lets the nucleus hold the shared pairs strongly — correct. Yes!
• Its large size lets it reach many atoms. Carbon atoms are small, not large. The small size is what lets the nucleus hold the shared pairs strongly.
• It has a very large number of protons. The book gives the reason as small size, not the number of protons.
• Stronger than carbon's bonds. The bonds formed by elements having bigger atoms are much weaker than carbon's.
• Much weaker — correct. Yes!
• Exactly as strong as carbon's. The book says they are much weaker.
• They are very reactive. The strong bonds make the compounds exceptionally stable.
• They are unable to form chains. Strong carbon-carbon bonds are what let carbon form long chains.
• They are exceptionally stable — correct. Yes!
• The small atom's — correct. Yes!
• The bigger atom's. The nucleus of a small atom holds the shared pair strongly, and bonds of bigger atoms are much weaker.
• Both hold it equally. Small atoms hold shared pairs strongly, while bonds of bigger atoms are much weaker.