chm 116 solids & modern materials

What are the 4 classifications of solids?

Metallic, ionic, covalent, molecular

Metallic Solids

Extended network of atoms held together by metallic bonds

What makes metals such good conductors?

Delocalized valence electrons

Ionic Solids

Extended network of atoms held together by ion-ion bonds

Covalent Solids

Extended network of atoms held together by covalent bonds

Molecular Solids

Discrete molecules held together by intermolecular forces

What are the 2 structures of solids?

Crystalline and amorphous

Which type of structure of solid has highly ordered molecules?

Crystalline

Which type of structure of solid has molecules with no order?

Amorphous

What fraction volume do center atoms have in cubic structures?

1

What fraction volume do face atoms have in cubic structures?

1/2

What fraction volume do edge atoms have in cubic structures?

1/4

What fraction volume do corner atoms have in cubic structures?

1/8

What’s the formula for a (side length) of a simple cubic structure?

a=2r

What’s the formula for a (side length) of a body-centered cubic structure?

a=4r/square root 3

What’s the formula for a (side length) of a face-centered cubic structure?

a=4r/square root 2

What are the coordination numbers for cubic, body-centered, and face-centered cubic structures?

6, 8, 12