Why `Sm^(2+), Eu^(2+)` and `Yb^(2+)` ions in solutions are good reducing agents?

(a) Separation of lanthanide elements is difficult. Explain. (b) Sm^(2+), Eu^(2+) and Yb^(2+) ions in solutions are good reducing agents but an aqueous solution of Ce^(4+) is a good oxidising agent. Why?

Why alkali metals used as reducing agents ?

In which reaction H_2O_2 acts reducing agent?

In SO_2 an oxidizing agent or reducing agent or both?

Why is aluminium a good reducing agent ? Give examples.

Why alkali metals act as strong reducing agents ?

H_2O_2 acts as a reducing agent in its:

In aqueous solution, H_2 does not reduce:

Explain with correct reason whether Sm^(2+) and Eu^(2+) act as good oxidising or reducing agent

Between SO_2 and SO_3 which one acts as the reducing agent ?