How is lithium chemically similar to alkaline-earth metals?

Although lithium is classified as an alkali metal in Group 1 of the periodic table, it exhibits several chemical similarities to alkaline-earth metals, particularly magnesium.1

These similarities arise primarily because lithium and magnesium possess comparable atomic and ionic radii. Key points of chemical resemblance include:1

• Oxidation Properties: Like alkaline-earth metals, lithium typically forms a monoxide when oxidized.1
• Organic Chemistry: The reactions of organolithium compounds are similar to the Grignard reactions performed with organomagnesium compounds, which serve as a standard synthetic procedure in organic chemistry.1

While lithium generally behaves like other alkali metals—such as being highly reactive with water and forming strong hydroxide solutions—these specific parallels with alkaline-earth elements distinguish its chemical behavior in certain contexts.1