S Block Elements



  • Group 1 elements are called alkali metals, which include lithium, sodium, potassium, rubidium, caesium, and francium.
  • Alkali metals react with water to form hydroxides that are strongly alkaline in nature.
  • Group 2 elements include beryllium, magnesium, calcium, strontium, barium, and radium.
  • Except for beryllium, Group 2 elements are known as alkaline earth metals because their oxides and hydroxides are alkaline in nature.
  • Sodium and potassium are abundant, while lithium, rubidium, and caesium have lower abundances.
  • Francium is highly radioactive and has a half-life of only 21 minutes.
  • Calcium and magnesium rank fifth and sixth in abundance respectively in the earth’s crust, while strontium and barium have lower abundances.
  • Beryllium is rare, and radium is the rarest of all, comprising only 10–10 per cent of igneous rocks.