Question

What is the fundamental thing that gives metals and non metals their properties

Answer 1

Iam giving you the reasons for the physical properties of metals and nonmetals...if the question was a bit more clear,more uniform answer will be given..

Metals:
Most metals are silvery looking, high density, relatively soft and easily deformed solids with good electrical and thermal conductivity, closely packed structures, low ionisation energies and electronegativities, and are found naturally in combined states.


Nonmetals:
Most are gases at room temperature; have relatively low densities; are poor electrical and thermal conductors; have relatively high ionisation energies and electronegativities; form acidic oxides; and are found naturally in uncombined states in large amounts.