Question

Why don't metals break when pounded into sheets or drawn into wires?

Answer 1

Because metallic bonding is non-localized, and extends throughout the metallic lattice. Metal nuclei can move with respect to other metal nuclei without disrupting the forces of attraction.

Explanation:

We are introduced to the notion of metallic bonding relatively early; i.e. positive ions in a sea of electrons, in which each metal centre donates 1 or 2 (or more) valence electrons to the overall metallic lattice and bonding is non-localized.

This notion of non-localized bonding explains (i) the electrical conductivity of metals (the electrons are free to move if a potential difference is applied); (ii) malleability, the metals may be hammered into a sheet; and (iii) ductility, the metals may be drawn into a wire. Electrons are the interstitial glue that gives rise to these properties.

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