Metallic and Ionic bonding.

Metals: -Good conductors of electricity -Good conductors of Heat -Lustrous or reflective when freshly cut or polished -Malleable ? can be shaped by beating -Ductile ? can be drawn into a wire -Exihibit a range of melting and boiling temperatures -Generally have high densities Exceptions in metals: -Mercury ? liquid at room temperature, unusually low melting point. -Chromium ? brittle rather than malleable. Structure of Metals Model of metal in solid state must be one in which: -Some of …

…oIn solid form, ions are held in position in the crystal lattice and are not free to move. oNo delocalized electrons, only localized electrons -Conduct electricity in Molten and Aqueous state oWhen solid melts, ions become free to move, movement of these charged particles to an electrode completes the circuit. oElectrons become localized and move to positive end of circuit. -Soluble in water oWhen NaCl dissolves in water, ions separate and are free to move