Water is composed of hydrogen and oxygen atoms bonded together as H2O molecules. The uneven distribution of charges within water molecules results in polarity, with the oxygen end slightly negative and hydrogen ends slightly positive. This allows opposing charges between molecules to form weak hydrogen bonds. Hydrogen bonding between water molecules absorbs heat energy and requires more energy to change water's state, especially during phase changes. It also results in water having a density of 1g/mL and being less dense as a solid than liquid. Hydrogen bonding and the resulting pockets account for these unique properties.

1. Notes:
Summarize: Five lines to write on
Width ~ 3 Fingers
Key Words and
Questions:
Water Notes

2. What is the
structure of
water?
• Composed of two hydrogen atoms and one oxygen
atoms
• H2O

3. Polarity:
• Unevenly distributed charges due to unequal forces
placed on bonding electrons
• Oxygen end slightly -, Hydrogen ends slightly +

4. Hydrogen
Bonding:
• Oppositely charged ends of water molecules attract
forming loose bonds

5. What are the
results of
hydrogen
bonding?
• Hydrogen bonds between molecules absorb heat
energy, therefore need more heat energy to change
temperature especially when changing phase

6. What is the
density of
water?:
• Water has a density of 1g/mL
• Less dense as solid than liquid (rare)
• Due to hydrogen bonding and resultant pockets

7. Cohesion:
• Hydrogen bonding locks water molecules together
• Surface Tension: Cohesion at the water’s surface

8. Adhesion:
• Adhesion: when water attaches to non-water molecules
ADHESION
C
O
H
E
S
I
O
N

9. Capillary
Action:
• Movement of water up

10. Salt vs.
Freshwater:
• Only 4% of water on Earth is fresh
• Most is inaccessible in glaciers