Metallic Bonds and the Properties of Metals (Chapter 6, Lesson 4) Flashcards
Electron Sea Model
all metal atoms in a metallic contribute their valence electrons to form a “sea” of electrons that surrounds the metal cations in the lattice.
The outer energy levels of the metals atoms overlap in…
a metal lattice
Delocalized electrons
the electrons in the outer energy levels of bonding metallic atoms
What happens when an atom’s outer electrons move throughout the solid?
a metallic cation is formed
Metallic Bond
the attraction of a metallic cation for delocalized electrons
Physical properties of metals
- melting and boiling points
- thermal and electrical conductivity
- malleability, ductility, and durability
- hardness and strength
(+ or o) Metals have moderately high melting points and high boiling points
+
Why are melting points of metals less extreme than boiling points?
The cations and electrons are mobile. Doesn’t take much energy to move them.
As the number of de localized electrons increases…
so does hardness and strength
Alloy
mixtures of elements that have metallic properties
(+ or o) alloys are the same as the properties of the elements that they contain
o, they differ
What are the two basic types alloy are classified into?
- substitutional alloy
- interstitial alloy
Substitutional alloy
some of the atoms in the original metal are replaced by other metals if similar atomic size
Interstitial alloy
formed when the small holes in a metallic crystal are formed with smaller atoms
