Which is most basic in character?

How does the ionization energy of Group $1$ elements change down the group?

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R).$
Assertion $(A):$ Lithium salts are hydrated.
Reason $(R):$ Lithium has higher polarising power than other alkali metal group members.
In the light of the above statements,choose the most appropriate answer from the options given below:

$Al$ vessels should not be cleaned with materials containing washing soda because .............

Which of the properties of alkali metals is not listed correctly?

Lithium shows diagonal relationship with