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Q.
Alkaline earth's metals are denser than alkali metals, because metallic bonding in alkaline earth's metal, is:
BHUBHU 2004
Solution:
Alkaline earth metals $(ns ^{2})$ are denser than alkali metals $(ns ^{1} )$ because metallic bonding in alkaline earth metals is stronger than alkali metals due to presence of two electrons in valence shell as compared to one electron in alkali metals.