Each element is represented by its own chemical symbol. A chemical symbol:
For example, the element mercury is shown as Hg. You must not show it as HG, hg or hG.
The periodic table shows the names and/or symbols of the elements. Elements are arranged into groups that share similar characteristics. Groups are numbered from 1 to 7, then 0.
Note that in the periodic table, metals are found on the left and non-metals are found on the right.
Names and formulae of some common ions:
|Name of ion||Ion formula||Electrical charge(s)|