Key learning points

1. Each column of the periodic table is called a group, and each row is called a period.
2. The periodic table was developed by a Russian scientist called Dimitri Mendeleev.
3. The periodic table contains all the elements organised into groups and periods, according to their properties.
4. The elements in the same group in the periodic table have similar properties.
5. In addition to groups, elements can be divided into non-metals and metals, which include the transition metals.

Keywords

• Periodic table - is a list of all known elements, ordered by increasing atomic number. It is split into vertical columns called groups, and horizontal rows called periods.

• Group - is a column on the periodic table that corresponds to the number of electrons in the outer shell of an atom.

• Period - is a horizontal row on the periodic table. Each period corresponds to a number of shells of electrons in an atom of an element.

• Transition metals - a group of metals found in the central block of the periodic table.

Common misconception