Atmospheric water and weather Flashcards
water is in _____ forms
visible and microscopic forms
only common substance to occur in all three states naturally
water
hydrologic/water cycle is the
movement of water throughout the atmosphere, hydrosphere/cryosphere, lithosphere and biosphere
what drives the water cycle
energy exchange (sun) and gravity
weather
short-term day to day conditions of the atmosphere
climate
long term average (30 years) of weather conditions and extremes in a region
meteorology
study of atmosphere (short term weather)
nature of the hydrogen-oxygen bond
oxygen bond gives hydrogen a slight positive charge and oxygen side a slight negative charge
water molecules are ____ to each other
attracted
what is the result of the slight charges in the hydrogen-oxygen bond
polarity
hydrogen bond
positive hydrogen side attracts the negative oxygen side
unique properties water has BECAUSE OF the hydrogen bonds
- surface tension
- capillarity
surface tension
allows objects with a higher density than water such as razor blades and insects to float on a water surface
capillarity
tendency because of the hydrogen bonding for water to “climb” the edges of glasses, and test tubes… or to move between soil particles
what must happen for water to change from one state to another
heat must be added or released from it
the amount of heat absorbed or released must be sufficient to
affect the hydrogen bond between molecules
what is important to atmospheric processes
the relation between water and heat energy
heat exchanged between physical states of water provides more than ____ of the energy that powers the general circulation of the atmosphere
30$%
phase change
each change between states of water
examples of phase changes between solid and lique
- melting
- freezing
what happens as water cools from room temp
it contracts in volume
it increases in density
why does cooling water increase in density
because the same number of molecules now occupy a smaller space
what state is water when its cooled to the point of greatest density (4 degrees celsius)
liquid state
what happens if cooling continues past 4 degrees celsius
it expands as more hydrogen bonds form among the slowing molecules
pure ice has _____ times the density of water
0.91
why does pure ice float
because it has 0.91 density of liquid water
characteristics of water in a liquid state
- non-compressible fluid
- assumes shape of the container
how can ice change to water
heat must increase the motion of water molecules enough to BREAK some hydrogen bonds
1 gram of ice needs _____ heat to become 1 gram of water (0 degrees Celsius)
80 calories of heat absorbed
1 gram of liquid water at 0 degrees Celsius has to absorb ____ heat to become 1 gram of liquid water at 100 degrees Celsius
100 calories absorbed
1 gram of water at 100 degrees celsius must absorb ____ heat to become 1 gram of water vapour at 100 degrees celsius
540 calories
1 gram of water vapour at 100 degrees celsius must ____ heat to become 1 gram of liquid water at 100 degrees Celsius
release 540 calories (-540 calories
1 gram of liquid water at 100 degrees Celsius has to ____ heat to become 1 gram of liquid water at 0 degrees Celsius
release 100 calories (-100)
1 gram of solid water at 0 degrees celsius needs _____ to become 1 gram of liquid water (0 degrees Celsius)
release 80 calories (-80)
latent heat
heat energy of a phase change
will temp increase while latent heat in changing state
NO
water vapour characteristics
- invisible
- compressible gas
- molecules are independent of each other
is water boiling point affected by air pressure differences
yes
latent heat of vaporization
amount of heat energy needed to change liquid to gas
latent heat of condensation
water vapour condenses to a liquid (540 calories