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Science

Group 1 and group 7 elements

Metals react with non-metals to form salts - for example, sodium chloride. When they are molten, these compounds conduct electricity, which shows that they are made up of charged particles called ions.

Metal ions

When a metal reacts with a non-metal, each metal atom loses the electron, or electrons, from its outer shell. The atom loses negative electrons but still has the same number of positive protons, so it has an overall positive charge. It's not an atom now. Instead it is called an ion. Here are some examples of metal ions:

Examples of metal ions

ElementAtom diagramIon diagram

Lithium, Li

Diagram of lithium atom

Lithium is in Group 1. It has one electron [electron: An electron is a very small negatively-charged particle found in an atom in the space surrounding the nucleus. ] in its outer shell.

Diagram of lithium ion

When this electron is lost, a lithium ion Li+ is formed. A lithium ion has the same electronic structure as a helium atom (He).

Sodium, Na

Diagram of sodium atom

Sodium is also in Group 1. It has one electron in its outer shell.

Diagram of sodium ion

When this electron is lost, a sodium ion Na+ is formed. A sodium ion has the same electronic structure as a neon atom (Ne).

Magnesium, Mg

Diagram of magnesium atom

Magnesium is in Group 2. It has two electrons in its outer shell.

Diagram of magnesium ion

When these electrons are lost, a magnesium ion Mg2+ is formed. A magnesium ion has the same electronic structure as a neon atom (Ne).

Calcium, Ca

Diagram of calcium atom

Calcium is also in Group 2. It has two electrons in its outer shell.

Diagram of calcium ion

When these electrons are lost, a calcium ion Ca2+ is formed. A calcium ion has the same electronic structure as an argon atom (Ar).

Back to Chemical patterns index

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