The Importance of Water & Carbon

Unique Properties of Water

1. Polar molecule (uneven distribution of electrons).
2. Oxygen is electronegative
3. It pulls electrons to itself in its covalent bond with hydrogen having a partial positive charge;
4. This uneven distribution of electrons creates a dipole.
5. Water molecules can interact with each other via hydrogen bonding (aka H-bonds). Due to H-bonds:
6. Water molecules are cohesive;
7. Water has a high heat capacity and boiling point;
8. Water will associate with other uncharged molecules that have polar covalent bonds and/or full charges on ions.

1. Solid less dense than liquid
2. Water assumes a lattice structure when solid;
3. This orderly arrangement allows for spaces between molecules;
4. Ice is 10% less dense than water.

1. "Universal solvent"
2. Water can surround polar or charged molecules to dissolve them. Example: in water, NaCl is broken into Na+ and Cl- ions, with water's negative partial charge surrounding the Na+, and positive partial charge surrounding the Cl-.
3. Substances that easily dissolve in water are hydrophilic: water loving.
4. Substances that do not dissolve well in water are hydrophobic.