Solids

Solids retain their shapes because they have rigid crystal structures. Based on the attractive forces that

hold tem together or on the arrangement of the atoms in the crystals themselves.

Solids

Crystal Types Based on Attractive Forces

Metallic crystals

Ionic crystals

Molecular crystals

Network (covalent) crystals

Amorphous (noncrystalline) substances

Solids

Metallic Crystals All metals in the periodic table are

solids at 25°C, except mercury. A rigid structure of metal nuclei and

inner electrons, valence electrons are very mobile, moving freely from atom to atom. Mobile e- bond atoms together with

widely varying degrees of force Fe, Cr, Co, Au, Pt, & Cu have MP

above 1000°C. Hg & Ga melt at or below room

temperature

Bi

Solids

Metallic crystals Mobile valence e- explain the ability of

metals to conduct heat & electricity Interaction of light with mobile valence

e- is responsible for a metal’s luster

Some metals (Pb, Au, Na, & K) are soft & can be cut with a knife

Others (Sn & Zn) are brittle Most metals are malleable & ductile These properties are due to crystal

structure- allow movement of atoms without a major disruption in the crystals

Malleable

Ductile