Question

softness of alkali metals increases from li to cs.

Answer 1

The group I of period table, comprising of Li ,Na, K,Rb,Cs and Fr are called as Alkali metals because on reacting with water they form strong Alkali.
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Softness of alkali metals increases from Li to cs.

Reason:
All Alkali metals are soft and can be cut with the help of knife
For example: sodium
Softness of Alkali metal is due to weak bonding in them as the result of large atomic size .
As we move down the group, the atomic size increases, thefore metallic bonding weakens and hence softness increases.
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