In 1st group, Li has the highest ionization potential but it must be understood that ionization potential is a property of an isolated atom in gaseous state. read more
li has highest hydration energy of lithium ion among alkali metals thats why lithium is strong reducing agent. The heat energy released when new bonds are made between the ions and water molecules is known as the hydration enthalpy of the ion. If the hydration enthalpy of an ion is high, it means that the hydrated ion is very stable. read more
Alkali metal have a strong tendency to lose electrons and act as good reducing agents. The reducing character increases from sodium to caesium. However lithium is the strongest reducing agent. Reason The alkali metals have low value of ionization energy which decreases down the group and so can easily lose their valence electron and thus act as good reducing agents. read more