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Ionic bonding

Ionic compounds

Group 1 and Group 7

The elements [element: A substance made of one type of atom only. ] in Group 1 of the Periodic Table are called the alkali metals. They form ionic compounds when they react with non-metals. Their ions have a single positive charge. For example, sodium forms sodium ions, Na+.

The elements in Group 7 of the Periodic Table are called the halogens. They form ionic compounds when they react with metals. Their ions have a single negative charge. For example, chlorine forms chloride ions, Cl–.

Sodium chloride

Ionic lattice of sodium chloride, showing positively charged sodium ions bonded to negatively charged chloride ions

Sodium chloride, NaCl, forms when sodium and chlorine react together. It contains oppositely charged ions held together by strong electrostatic [electrostatic: An electrostatic force is generated by differences in electric charge (ie positive and negative) between two particles. It can also refer to electricity at rest. ] forces of attraction – the ionic bonds. The ions form a regular lattice [lattice: A lattice is a regular grid-like arrangement of atoms in a material. ] in which the ionic bonds act in all directions.

Back to Structure and bonding index

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