The single outer electron is further away from the nucleus and thus is less tightly bound and thus it is energetically easier to remove that electron
Rb
Li+ , Na+ , K+ , Rb+ , Cs+ , Fr+
1
the order of reducing capacities is: Na<K-Rb<Cs<Li
These six elements are Li, Na, K, Rb, Cs and Fr.
Smallest to largest is going down the group 1. I.e. Li is smallest<Rb<Cs
These elements are: K, Rb, Cs, Fr, Ra.
Ca, Mg, Be, Fr, Cs, Rb, K, Na, Li, H
Rb
Li+ , Na+ , K+ , Rb+ , Cs+ , Fr+
Rubidium, Cesium, Francium
The donor
H Li Na K Rb Cs Fr
The alkali metals are: Li, Na, K, Rb, Cs, Fr.
H Li Na K Rb Cs
Li Na K Rb Cs Fr (hope this is help)
group 1 is Li, Na, K, Rb, Cs and Fr.