1. Properties of Water
Chapter 3

2. Overview of H20’s properties
Resulting from hydrogen bonding:
Cohesion/Adhesion/Surface tension
High specific heat (temperature moderation)
Density is lower as a solid than as a liquid
Universal solvent
Neutral pH

3. Cohesion/surface tension
Water molecules are attracted together due to weak hydrogen bonding.
Surface tension:
how difficult it is to stretch or break a surface

4. Adhesion/Relevance Adhesion: Relevance:
Water molecules are attracted to to other materials due to weak hydrogen bonding.
Relevance:
Poured/make waterfalls/waves, etc. (Cohesion)
No energy is required for water to move up the stem of a plant (cohesion & adhesion)

5. Specific Heat
the amount of heat energy required to bring 1 g of substance up 1 °C.
Water sets the standard.
Water’s = 1.

6. Specific Heat of Water Water’s specific heat is 1
Water heats & cools slowly because of its high specific heat
due to hydrogen bonding
it’s cooler by the Lake.
freeze
boil

8. Density Liquid water’s density=1.00 g/cm3 Ice’s density is 0.92 g/cm3
As water freezes, it becomes more dense, until it reaches the highest density at 4 degrees.
Then, it crystallizes & expands from 4-0 degrees, so it floats.

9. Universal solvent Most substances dissolve in water.
Esp. ionic and polar molecules
Nonpolar substances (like oil) do not dissolve in water.
Solute + Solvent = Solution

10. Water is neutral Water has a pH of 7.
Living things survive best in pH near 7