* Smaller atomic size: Aluminum atoms are smaller than sodium atoms. This means that the aluminum nucleus has a stronger attraction to the valence electrons, leading to a higher electron density in the metallic lattice.
* Higher number of valence electrons: Aluminum has three valence electrons, while sodium has only one. This means that aluminum has more electrons available to participate in the metallic bond, leading to a stronger bond.
* Higher charge density: The smaller size and higher number of valence electrons in aluminum result in a higher charge density within the metallic lattice. This greater concentration of charge strengthens the attractive forces between the positive metal ions and the delocalized electrons.
In summary: The combination of smaller atomic size, higher number of valence electrons, and higher charge density in aluminum leads to a stronger metallic bond compared to sodium. This results in aluminum having higher melting point, higher boiling point, and being stronger and more resistant to deformation than sodium.
