Part By: Felipe De la Garza

Chemistry House

Silicon (Si)

• Group 4

• 4 valence electrons

• Silica

• Quartz

• Giant Covalent structure

• Tetrahedral arrangement

• Glass: 75% SiO2

Silicon Dioxide

Silicon Dioxide

Electrostatic Attraction in Metallic Bonds

• Delocalized electrons

• "Sea of electrons"

• ⚡

• Metal cations

Conductivity in Metallic Bonds

• Conductivity: ions that are able to move & carry a charge

• Metals have a "pool" of electrons

Copper (Cu)

VSEPRValence Shell Electron Pair Repulsion

• electron pairs formed in the valence shell of atoms repel each other and thus position themselves as far apart as possible

• A molecule's geometry is determined by its electron pairs' repulsion

• Predictions of molecular shape

Negative Charge Centers

• Two NCC

• Molecules with two charge centers will place them 180' from each other. Thus, the molecule has a 180' linear shape

• BeCl2: Cl—Be—Cl

• C2H2:

Negative Charge Centers

• Three NCC

• Molecules with three charge centers will place them 120' from each other. Thus, giving a planar triangular shape to the distribution of electrons.

• If all NCC are bonded, the shape will also be planar triangular

• If one of the pairs is not bonded, it will result in a bent structure.

117'

Negative Charge Centers

• Four NCC

• Molecules with four charge centers will place them 109.5' from each other. Thus, giving a tetrahedral shape to the electron pairs

• Tetrahedral

• Trigonal pyramidal

• Bent or "V" shaped