Question

How do you determine if a substance has metallic bonds?

Answer 1

In a metallic substance there are special forces which hold atoms together and they are called metallic bonds. When it comes to solid, we can see that the atoms are very close to each other in the arrangement and are found to make up a definite shape. This happens as the outermost electron shell of each metal atom often overlaps with a neighbouring atom.

Complete answer:
Pure metals are solids with crystalline structure. They are not like ionic compounds ad instead at every point in the crystal lattice, there is a presence of an identical atom the valence electrons are the ones present in the outermost energy level of any atom and thus they are capable to move and drift from one metal atom to another.
This is formed when the valence electrons continually move from one atom to another and are no longer associated with any specific pair of atoms. The valence electrons present in metals are non-localized which means they are capable of wandering freely across the whole crystal. When electrons move around, they leave behind atoms which have now become positive ions and this interaction between the newly formed ions and the moving electrons causes the generation of a cohesive or binding force which holds the metallic crystal at one place.
Due to these moving electrons, metal can conduct electricity and thus show metallic bond properties.

Note:
A metallic bond is the attraction which is present between a stationary metal cation and its surrounding mobile electrons. Metallic bonds involve electrons that are delocalized through the volume of the material. So the metallic bonds can be seen as good electrical conductivity at ambient temperature.