Write three general characteristics of the elements of s-block of the periodic table which distinguish them from the elements of the other blocks.

The three general characteristics are:

(1)The compounds of the s-block elements are mainly ionic.

(2)The valency is equal to the group number.

(3) Due to low ionization energy, s-block elements are good reducing agents.

The alkali metals have low densities. Explain. ?

The alkali metals have low densities due to their large atomic sizes. In fact, Li, Na and K are even lighter than water.