Differences between alkali metals and alkaline earth metals

Alkali metals (Group 1) and alkaline earth metals (Group 2) are both part of the s-block elements, but they have some key differences:

• Valence Electrons: Alkali metals have one valence electron in their outermost s-orbital, while alkaline earth metals have two.
• Reactivity: Alkali metals are more reactive than alkaline earth metals. For example, sodium (an alkali metal) reacts more vigorously with water than magnesium (an alkaline earth metal).
• Ionization Enthalpy: Alkali metals have lower ionization enthalpy compared to alkaline earth metals, making it easier for them to lose their outermost electron.
• Hardness: Alkaline earth metals are generally harder than alkali metals.
• Melting and Boiling Points: Alkaline earth metals have higher melting and boiling points compared to alkali metals.
• Oxides: Alkali metals form strong bases like NaOH when their oxides dissolve in water, whereas alkaline earth metals form less strong bases like Ca(OH)₂.