Section 4 Flashcards
(17 cards)
What is surface tension?
Surface tension is the tendency for the molecules of a substance (liquid) to be pulled from the surface to the interior.
Why does water have very high surface tension?
Because water has high cohesive and adhesive forces of attraction.
Which organism can use water’s high surface tension to its advantage?
Water strider.
What makes water unique in terms of its states?
Water is one of the only substances that can exist in all three states (phases) at the same time.
What happens during a change of state in water?
Each change of state involves an exchange of energy with the surroundings.
What is the range between the melting and boiling points of water?
There is a large range between melting (0°C) and boiling (100°C).
Why is this large temperature range important?
It allows for a wide range of temperatures on Earth without dramatic changes in body temperatures, state, climate, etc
How is water unique in terms of density?
Water is less dense as a solid.
At what temperature is water most dense?
At 4°C.
Why is the density of water important for aquatic life?
It allows lakes to freeze at the top while the densest water (4°C) sinks to the bottom, helping aquatic life survive in winter
According to the 2nd Law of Thermodynamics, in which direction does heat move?
Heat always moves from matter at a high temperature to matter at a low temperature.
What is specific heat capacity?
It is the amount of heat energy required to change the temperature of a specific mass of a substance by 1°C.
Why is water’s specific heat capacity important?
Water has a very large specific heat capacity, which means it takes a lot of energy to change its temperature.
How does water’s high specific heat capacity help warm-blooded animals?
It helps them maintain a constant body temperature.
What role does water play in Earth’s climate?
It moderates global climate.
Why do cities at the same latitudes sometimes have different climates?
Because of their proximity to a large body of water and the presence of ocean currents.
What two main factors influence the climate of cities near the ocean?
A large body of water and ocean currents.
Examples Vancouver, Labrador, lethbridge
