Order of Elements in the Modern Periodic Table

Here’s a breakdown of the order of elements in the Modern Periodic Table:

The Periodic Law

• The modern periodic table is arranged according to the periodic law, which states that when elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.

Groups (Vertical Columns)

• Elements in the same group (vertical column) have the same number of electrons in their outer shell. This is also known as valence electrons.
• This arrangement results in groups having elements with similar chemical properties because the number of valence electrons influences an atom’s chemical reactivity.

Periods (Horizontal Rows)

• A period (horizontal row) in the periodic table of elements indicates a complete shell of electrons.
• Elements in the same period have the same number of electron shells.
• As you move across a period, the properties of the elements gradually change.

Transition Metals

• The block in the middle of the table includes the transition metals.
• Transition metals are characterised by variable oxidation states, formation of coloured compounds, and good conductivity of heat and electricity.

Noble Gases

• The elements in Group 18 of the periodic table are known as the noble gases.
• These elements are notable for their very low reactivity due to having full outer electron shells.

Use this structure as a guide when endeavouring to understand and remember the order and arrangement of elements in the modern periodic table.