Metallic Bonding Photo by Magnus Manske Photo by Materialscientist

Ionic Compounds Metals lose/donate electrons and nonmetals gain/accept electrons. This is why metals react with nonmetals to create IONIC COMPOUNDS. NaCl Sodium Chloride

The ions in an ionic compounds arrange themselves into crystals The ions in an ionic compounds arrange themselves into crystals. These salt crystals form a lattice structure that depends on the ratio and type of ions. Each ion forms an ionic bond with the ions around itself.

Covalent Compounds Sharing electrons creates covalently bonds. The elements in a molecule cannot break apart without losing the electrons they are sharing, so they remain together. This makes covalent bonds much stronger than ionic bonds.

Covalent compounds are arranged into individual molecules. These molecules interact with each other, but these interactions are typically very weak.

Metallic Bonding The atoms in a metal stay together in a unique way. Inside of a sample of metal, the outer energy levels of each atom overlap creating one gigantic electron cloud. Because of this, the electrons do not have to stay around one atom. These delocalized electrons travel around all of the atoms.

Delocalized Electrons Because of this delocalization of electrons, the atoms in a metal sample share electrons in way analogous to covalent bonds, and they arrange themselves in a repeating pattern similar to ionic bonding. Metallic bonding is a unique blend of both types of bonds. Free High School Science Texts Atomic combinations: Metallic bonding

Because these delocalized electrons are already freely moving around the metal atoms, they respond very easily to differences in electrical voltages. This is why metals are such good conductors of electricity. Electrons freely move through the giant electron cloud.

These facts make metals good conductors of heat. Because these delocalized electrons are freely moving, adding heat easily increases their kinetic energy. The lattice structure of metals also allows vibrations to pass easily from atom to atom. These facts make metals good conductors of heat.

Because electrons are freely shared between all atoms of a metal, there are no true metallic bonds between atoms. This is why the atoms of a metal can be easily deformed. The attraction between two atoms can be broken since they are just as attracted to the next atom. Photo by Arcimboldo

malleable ductile malleable ductile The delocalization of electrons allows metals to be deformed and reshaped. This makes metals both malleable and ductile. Malleability means that the metal can be bent and is pliable without breaking or cracking. Extremely malleable metals can be formed into this sheets. Ductility is the ability to be drawn into a wire.

An alloy is made when metals are mixed together. Adding different metals affects the arrangement of the metal atoms. This altered arrangement of atoms can be more or less stable. This can make the alloy stronger or weaker than the metal was by itself. Steel (Iron and Nickel Alloy) Brass (Copper and Zinc Alloy) Bronze (Copper and Tin Alloy)

Is melting a physical change or Important Fact: An alloy is made when metals are evenly mixed together. The metals are melted together and mixed. They can be separated by melting the alloy. Is melting a physical change or chemical change? Melting is a physical change. This means that alloys are NOT a new substance. They are simply a homogeneous mixture of substances.

Melting Metals When a solid substance like iron has been melted, it becomes a liquid. Scientists call a fully melted solid the molten form of the substance. Molten iron and molten nickel are mixed together and allowed to cool back into solids in order to make the mixture of steel (an alloy). Molten Iron