C5 - Chemicals of the Natural Environment
Chemicals in the Atmosphere
Dry Air is a Mixture of Gases
78% Nitrogen
21% Oxygen
1% Argon
0.04% Carbon Dioxide
Molecular Substances
Molecular Substances Have Low Melting and Boiling Points
Atoms within the molecules are held together by very stong covalent bonds
The attractions between the molecules are very weak
Usually gases and liquids at room temperature
Chemicals in the Hydrosphere
The Earth's Hydrosphere is in the Oceans
Identifying Negative Ions
Metals From Minerals
Calculating Masses
Environmental Impact
Covalent Bonding
Covalent Bonds - SHARING electons
Want to make a full outer shell
Due to electrostatic attraction between the positive nuclei and the negative electrons shared between them
Eg, Hydrogen H2
Eg, Carbon Dioxide CO2