Chapter 3 Flashcards
What role do streams play in the water cycle?
They affect and ARE affected by precipitation, groundwater, evaporation, etc.
What is the water cycle?
A movement between sinks and fluxs
What is a reservoir/sink? List them (6)
Where water is typically held for an extended period of time.
Ocean
Groundwater
Polar Ice/Glaciers
Atmosphere
Soil moisture
Lakes
What is a flux? List them (6)
Movement of water from one reservoir to another.
Precipitation
Evaporation
Evapotranspiration
Vapor transport (aka clouds)
Precipitation
Rivers
Why is a river a flux and not a sink?
Because a river is taking water from one sink to another.
Why is water polar?
Due to the electronegativity of oxygen pulling unevenly on the less electronegative hydrogen, resulting in areas of positive/negative.
How many protons & electrons does oxygen have?
8 protons, 8 electrons. 6 of the 8 electrons are valence electrons
How many protons & electrons does hydrogen have?
1 proton, 1 electron
What is the relative strength of a hydrogen bond? (compared to other IMFs and covalent/ionic bonds)
A hydrogen bond is relatively weak. Stronger than most IMFs. However, many hydrogen bonds together are very strong.
List the 5 most important properties of water
High specific heat
Cohesion
Viscosity
Buoyancy
Pressure
How does high specific heat affect aquatic life?
Buffers water temperature for cold-blooded aquatic animals
What is specific heat? What does high specific heat mean in terms of water?
How many calories does it take to raise 1g of X substance by 1C?
It takes 1 cal to raise 1g of water by 1C. This means water can store large amounts of heat energy with only a small increase in temperature
Why is water special in terms of changing states of matter?
Changing states of matter requires large amounts of heat energy due to high specific heat.
only 1cal reduces 1g of water by 1C, HOWEVER, if you wish to hit 0C, you must put 80cal of energy in to reduce 1g of water by 1C to 0C and turn it into ice.
Why does ice float?
A lattice is formed by hydrogen bonding, so they spread out further when they turn to ice. THis causes ice molecules to be less dense than liquid.
At what temperature is water most dense?
4C
What is cohesion? What does it produce?
Water molecules on the surface bond more strongly to water molecules below. Produces surface tension
What is surface tension?
Surface of water is “tight” and creates a barrier to small organisms (this also allows other organisms to walk on water!)
What is viscosity? What is the difference between water and air?
Force required for an object to move through liquid. Water has a frictional resistance 100x greater than air