What are alkali metals?

All the elements present in the first group of the periodic table are called alkali metals.

The alkali metals from top to bottom are:

• Hydrogen (H)
• Lithium (Li)
• Sodium (Na)
• Potassium (K)
• Rubidium (Rb)
• Cesium (Cs)
• Francium (Fr)

Since alkali metals are present in the first group, they have the same number of valence electrons in their atoms. For the same reason alkali metals show similarity in physical and chemical properties. For example, alkali metals all have a valency of +1, alkali metals are all transparent white lustrous metals, alkali metals are highly chemically reactive; They react with oxygen as soon as they are exposed to air, react with water to form their respective hydroxides; Their hydroxides are all strong alkali's.