Differences with alkali Metals
Non-metal: Hydrogen is essentially not a metal like all alkali metals, but a non-metal
Loss of Electron: Although it has only one electron in its outer shell, hydrogen cannot easily lose this electron to gain electropositivity. All other alkali metals can do this with ease.
State: At room temperatures where all alkali metals exist is the solid state, hydrogen is a gas.
size of atom: The H+ ion of hydrogen is much smaller than ions of alkali metals. Ionization
Potential: The ionization potential of hydrogen is over 300 kcal per mole, The maximum ionization potential for metals is 147 kcal per mole
