S-block

S-Block

• S-Block has two groups.

• First group is known as alkali metal and second group is known as alkaline earth metal.

• Element of first group is Li, Na, K, Rb, Cs, Fr and element of second group is Be, Mg, Ca, Sr, Ba, Rn.

• Electron configuration for First group: ns¹ and for second group: ns².

• S-Block has lower electron gain enthalpy ,lower ionisation enthalpy and lower electronegativity.

• Shape of S-Block is circular and it is non-directional.

• Magnesium is sixth and sodium is seventh most abundant element in the crystal rocks.

• These are fourth and fifth most abundant metals after Al, Fe, Ca.

• Potassium is the next most abundant element after sodium.

• All alkali metals exhibit an oxidation state of +1 in  their compounds.

• All alkaline earth metal has an oxidation state of +2 in their compounds

• The alkali metal has high chemical reactivity because it has lower ionisation enthalpy and lower enthalpy of atomisation.