Three Chemical Bonds: Romance Abounds!

There are three we must know, and we’ll explore them with romance!

 

 

We see this notably in water, protein structure, and nucleic acids. A hydrogen is attracted to an electrical pull from a lone pair (two “free” electrons on another element) from across the room. But this infatuation is easily “broken.”

 

On an H₂O molecule, an oxygen is bonded to two hydrogens on one side, but still has electrons left over – they are not bonded. Each lone pair causes the oxygen to turn its attention to other hydrogens – an H around the corner, and an H across the street. The oxygen raises its eyebrows at one of these cute hydrogens, but it sheepishly replies, “But I’m already bonded!”. Turns out that it shares a bond with its own oxygen, who scowls jealously. Throughout this town of H₂O, oxygen’s lone pairs are making eyes at other hydrogens, and hydrogens feeling the pull of romance from oxygens. This drama repeats itself across a literal sea of H₂O molecules. It creates a web of tension, which is why water behaves the way it does! Does that blow your mind?

 

 

The desire for eight valence electrons pulls these atoms together, but they borrow more than share. It’s a bond between a metal + non-metal.

 

A metal, sodium, with its one valence electron says, “I need you! Don’t leave!”

A non-metal, chlorine, gently hugs the sodium says gently, “It’s been a good electron, you and I…” with its 7 valence electrons orbiting. But it tugs on this one valence electron of sodium’s. It’s a rocky relationship.

 

This ionic bond creates NaCl, or salt. It’s written as Na+ [Cl]- with chlorine’s seven electrons in a Lewis dot structure inside the brackets.

 

Strongest bond: Covalent bond. (This is true love!)

 

One covalent bond represents two shared electrons. The more pairs, the stronger the molecule is. Remember the Octet Rule? Two non-metals in love is a beautiful thing (no offense to music fans). Remember that bonds are made and broken often, but some more than others!

 

An example of a single bond is H₂, hydrogen and hydrogen. The little orbs share two electrons in the middle, smiling happily together.

 

A double bond is O₂, oxygen and oxygen. These two orbs share two lone pairs, or four electrons, in the middle. They gaze into each other’s eyes.

 

A triple bond is N₂, nitrogen and nitrogen. They kiss passionately, saying “Never let me go!”. They share three lone pairs, or six electrons.

 

Note that not all covalent bonds are between the same elements, but these are really easy examples. Another great triple bond (now celebrating their 50th anniversary!) is carbon to oxygen, or C — O. They settled down, unlike those homewrecking hydrogens.