Atoms and Bonding

Composition of the Sun

Abundance of Light Elements Rarity of Lithium, Beryllium, Boron Preference for Even Numbers Abundance peak at Iron, trailing off after

How Elements Form in Stars Sun: 4 H  He He + particle  Mass 5 – Unstable He + He  Mass 8 – Unstable He + He + He  C Add more He to make heavier elements End of the line is iron for energy production Atoms beyond Iron made in massive stars

What are Planets Made of? Same material as Sun Minus the elements that remain mostly in gases We find this pattern in a certain class of meteorites (Carbonaceous Chondrites)

Chondrites

The Earth’s Crust looks Very Different

Composition of the Crust

Minerals are the Chemicals that make up the Earth Naturally-occurring Inorganic Chemical Compounds About 3000 Known 200 Common 20 Rock-forming

Atomic Bonding 1. Ions

Atomic Bonding 2. Electrical Neutrality (+) and (-) Cancel Out 3. Bonding (Satisfy 1 & 2) Ionic (NaCl) Covalent (O 2 ) Metallic (Cu, Al, Fe) Hydrogen (in water)

Ionic and Covalent Bonding

Metallic Bonding

Hydrogen Bonding

Summary of Bonding Ionic bonding holds rocks and minerals together Covalent bonding holds people and other organisms together Metallic bonding holds civilization together Hydrogen bonding gives water its heat- retaining and solvent properties

4. Lattices Atoms in crystals form a repeating pattern called a Lattice

5. Complex Anions Many minerals contain groups of atoms that behave as single units

What Do Atoms “Really” Look Like?

Standing Waves

The wave is everywhere in the tank, all the time The negative portions are just as real as the positive portions Other waves could be present in the same space at the same time

s-orbitals (Lithium and Beryllium)

p-orbitals

Boron, Carbon, Nitrogen

1s2s2p3s Sodium, Calcium

Carbon and Silicon

1s2s2p3s3p Phosphorus through Argon

Hybrid Orbitals: Carbon