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#Aluminium melting point free#

When sodium atoms come together, the electron in the 3s atomic orbital of one sodium atom shares space with the corresponding electron on a neighboring atom to form a molecular orbital - in much the same sort of way that a covalent bond is formed. Sodium has the electronic structure 1s 22s 22p 63s 1. Even a metal like sodium (melting point 97.8☌) melts at a considerably higher temperature than the element (neon) which precedes it in the Periodic Table. Metals tend to have high melting points and boiling points suggesting strong bonds between the atoms.

#Aluminium melting point free#

Drude's electron sea model assumed that valence electrons were free to move in metals, quantum mechanical calculations told us why this happened. As it did for Lewis' octet rule, the quantum revolution of the 1930s told us about the underlying chemistry. It is, however, a useful qualitative model of metallic bonding even to this day.

Conductivity: Since the electrons are free, if electrons from an outside source were pushed into a metal wire at one end, the electrons would move through the wire and come out at the other end at the same rate (conductivity is the movement of charge).Īmazingly, Drude's electron sea model predates Rutherford's nuclear model of the atom and Lewis' octet rule.

Electrons on the surface can bounce back light at the same frequency that the light hits the surface, therefore the metal appears to be shiny.

Luster: The free electrons can absorb photons in the "sea," so metals are opaque-looking.

Heat capacity: This is explained by the ability of free electrons to move about the solid.

The protons may be rearranged but the sea of electrons with adjust to the new formation of protons and keep the metal intact.

Malleability and Ductility: The sea of electrons surrounding the protons act like a cushion, and so when the metal is hammered on, for instance, the over all composition of the structure of the metal is not harmed or changed.

This model assumes that the valence electrons do not interact with each other. For example: metallic cations are shown in green surrounded by a "sea" of electrons, shown in purple.

In this model, the valence electrons are free, delocalized, mobile, and not associated with any particular atom. In the 1900's, Paul Drüde came up with the sea of electrons theory by modeling metals as a mixture of atomic cores (atomic cores = positive nuclei + inner shell of electrons) and valence electrons. Metals that are ductile can be drawn into wires, for example: copper wire.

Metals that are malleable can be beaten into thin sheets, for example: aluminum foil.Their physical properties include a lustrous (shiny) appearance, and they are malleable and ductile. Metals have several qualities that are unique, such as the ability to conduct electricity, a low ionization energy, and a low electronegativity (so they will give up electrons easily, i.e., they are cations).