Why Atoms Bond

Part of the Structure and Bonding section of Coddy's Chemistry journey. Lesson 1 of 49.

Atoms bond to reach a full outer shell, the arrangement of the noble gases.

Neon with shells 2, 8 and a full outer shell, beside sodium with shells 2, 8, 1

Neon has a full outer shell; sodium has one electron more

Sodium can give away its one outer electron; chlorine can take one more. Either way, each ends with a full outer shell.

Three kinds of bond: ionic (a metal gives electrons to a non-metal), covalent (non-metals share electrons) and metallic (metal atoms pool their outer electrons).

Challenge

A chlorine atom takes one electron and ends with a full outer shell, like argon. Arrange the electrons of the chloride ion, Cl⁻, in shells.

Try it yourself

Electron shellsFill the electrons of Cl− (chlorine)

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Structure and Bonding

1Ionic Bonding

Why Atoms BondForming Ions The Ionic Bond Ionic Formulas Polyatomic Ions Ionic Lattices Recap - Salt Factory

4Polarity

Electronegativity and Bonds Polar and Non-polar Bonds Ionic or Covalent Polar Molecules When Dipoles Cancel Recap - Dipole Hunt

7Functional Groups

Carbon Chains Structural Formulas Alcohols Carboxylic Acids Esters and Ethers Aldehydes, Ketones, Amines Recap - Group Finder

2Covalent Bonds

Sharing Electrons Counting Valence Electrons Drawing Lewis Structures Double and Triple Bonds Lone Pairs Formal Charge Lewis Structures of Ions Recap - Molecule Builder

5Forces Between Molecules

London Forces Dipole-Dipole Forces Hydrogen Bonds Boiling Points Like Dissolves Like Recap - Boiling Contest

8Practice Problems

Recap - Polar Bonds Survey Recap - Pigments and Hexane Recap - Butanol and Ether Recap - Dots on an Oxide

3Shapes of Molecules

Electron Groups Linear and Trigonal Planar Tetrahedral Molecules Pyramids and Bent Molecules Bond Angles Recap - Shape Detective

6Metals and Giant Structures

Metallic Bonding Diamond and Graphite Giant Covalent Structures Four Kinds of Substance Recap - Material Match