water’s angular shape and hydgrogen-bonding characteristics give it extra-ordinary properties
· the following table summarizes, explains, describes the effects, and gives an example of each unique property of water:
What Water Does |
Property |
Explanation |
Result |
Example |
water clings
|
cohesion
|
hydrogen bonds form between water molecules
|
Great surface tension |
a tooth pick floats on water |
adhesion
|
hydrogen bonds form between water molecules and other polar materials
|
capillary action |
water climbs up xylem of trees
|
|
water holds onto heat |
relatively high specific heat capacity
|
hydrogen bonding causes water to take in large amounts of heat before its temperature is increases and also causes it to lose large amounts of heat before its temperature decreases significantly
|
maintenance of temperature |
high heat capacity helps organisms maintain a constant body temperature |
high specific heat of vaporization
|
hydrogen bonding causes liquid water to absorb a large amount of heat to become a vapour (gas)
|
evaporative cooling |
many organisms, including humans, lose body heat by evaporation of water from surfaces, such as skin (by sweating) and tongue (by panting)
|
|
solid water is less dense than liquid water
|
highest density at 4˚C |
as water molecules cool below 0˚C, they form a crystalline lattice (freezing) – the hydrogen bonds between the V-shaped molecules spread the molecules apart, reducing the density below that of liquid water |
ice floats on liquid water |
fish and other aquatic organisms are able to survive in winter |