5. Water Notes

Water Notes:

Water:

Composed of two hydrogen atoms and one oxygen atoms

H2OPolar Molecule

Polarity:

Unevenly distributed charges due to unequal forces placed on bonding electrons

Oxygen ends slightly negativeHydrogen end slightly positive

Results of Polarity:

Allows water to form Hydrogen Bonds

Result of Polarity:

Hydrophilic: All polar molecules attracted to water

Result of Polarity:

Hydrophobic: Repels non-polar substances such as water

Stabilizes Temperature:

Hydrogen bonds between molecules absorb heat energy, thus molecules do not move faster, therefore temperature does not rise as quickly

Need more heat energy to change temperature

Cohesiveness:

Hydrogen bonding locks molecules together

Surface Tension: Cohesion at the water’s surface

Cohesiveness:

Adhesion: when water attaches to non-water molecules

ADHESION

COHESION

Cohesiveness:

Capillary Action: Movement of water up

Universal Solvent:

Ions and polar molecules readily dissolve in water

Substances such as salt are pulled apart by attraction of opposite charges due to polar structures

Density:

Water has a density of 1g/mLOne of the few substances that is less

dense as a solid than liquidDue to hydrogen bonding and resultant

pockets