A metal holds together. Its electrons can move.
Copper is used for electrical wires, and gold can be beaten into sheets thinner than paper. A salt crystal, by contrast, shatters when struck, and solid salt does not conduct. These differences come from how the particles are held together. Inside an atom there is a positive nucleus, with negative electrons in shells around it. Metal atoms such as sodium and copper have only a few electrons in their outer shell, and these are held quite loosely; the Bohr atom page shows those shells. In a metal, those outer electrons are not tied to any single atom, and that one fact explains both the conducting and the bending. Compare this with the ionic and covalent pages, where electrons are transferred or shared between particular atoms.
There are two kinds of parts in the model. Give each an identity before following it. A positive ion core contains a nucleus and the electrons still held near it, with a positive charge overall. Other electrons can move through the metal. When a supply is connected, follow those moving electrons to see how charge travels along the wire. Bending asks a different question: when one layer of cores slides past another, does the attraction holding them together remain? The same picture can help answer both, giving conducting and bending a reason we can return to.
01Meet the lattice and its shared electrons
The silver spheres are positive ion cores: a nucleus with its tightly bound inner electrons. Some outer electrons are delocalised—they do not belong to one particular atom. The attraction between these negative electrons and the positive cores is metallic bonding. The fine blue links below make this collective attraction visible; they are not individual, permanent bonds.
Model key: a schematic monovalent metal, 45 cores and 45 delocalised-electron markers. Core sizes, electron paths, drift speed and attraction links are teaching symbols, not atomic-scale trajectories or a quantitative conductivity calculation. The simple lattice does not specify copper’s actual crystal structure.
02Read the properties from the model
Electrical conduction
Connecting a supply sets up an electric field: a push along the wire that acts on the electrons. The field biases the motion of the mobile (delocalised) electrons, so charge moves without the whole solid moving. Reversing the field reverses both current and electron drift. By convention, current direction is the direction in which positive charge would move; electrons are negative, so electron drift is opposite to the current.
Malleability
Bend a copper wire into a new shape and it does not shatter the way a salt crystal does. Metal can change shape because layers can rearrange while sharing mobile electrons. The attraction is spread throughout the solid, rather than tied to a single pair of atoms.
Attraction is mutual
Cores attract the electrons; electrons attract the cores. The stable spacing also depends on repulsive and quantum effects. Attraction alone would not explain why matter has a finite size.
Check: if the current points right, which way do the electrons drift?
Left. Electrons carry negative charge, while conventional current uses the positive-charge direction. The local motion and much smaller net drift are different ideas.
