The elements in the periodic table combine in different ways to form everything around us. In the periodic table, elements are arranged in order of increasing atomic number. This is the number of protons in the nucleus of an atom.
Each element is represented by a unique box that includes its name, atomic number, chemical symbol, and atomic mass.
Elements in the periodic table are organised by periods and groups.
Periods are the horizontal rows and there are seven in total. These rows represent the number of electron shells that an atom has. For example, elements in period 3 have 3 electron shells.
Groups are the vertical columns. They are usually labelled from 1 to 18, although in some versions, the main groups are labelled 1-8 with the final group being called group 0 or group 8. Groups show how many electrons an atom has in its outermost shell. For example, elements in group 2 have two electrons in their outermost shell.