Chapter 3 Flashcards
How many times is water mentioned in the Bible?
about 620 (NIV)
Pslam 18:16
“He (the Lord) reached down from on high and took hold of me; he drew me out of deep water.”
Water
- biological medium here on Earth
- all living organisms require water more than any other substance
- 3/4 of the Earth’s surface is submerged in water
The abundance of water
main reason the Earth is habitable
John 7:37-38
“Jesus said, ‘If anyone is thirsty, let him come to me and drink. Whoever believes in me, as the Scripture has said, streams of living water will flow from within him.’”
Water as a polar molecule
- from electronegativities
- formed from hydrogen bonds with each other
- contributes to the various properties water exhibits
4 emergent properties of water that contribute to the Earth’s fitness for life
1) Cohesion
2) Temperature moderation
3) Insulation (expansion upon freezing)
4) Solvent of life (dissolves things well)
Cohesion
the bonding of a high percentage of water molecules to neighboring molecules and is due to hydrogen bonding
-helps the transport of water against gravity in plants by pulling water through their vessels
Adhesion
an attraction between different substances
-i.e. between water and plant cell walls
Surface Tension
a measure of how hard it is to break the surface of a liquid and is related to cohesion
- can be moved and pulled
Water moderates air temp
- by adsorbing heat from air that is warmer and releasing the stored heat to air that is cooler
- water can absorb or release a large amount of heat with only a slight change in its own temperature
Temperature
the measure of the intensity of heat
Kinetic Energy
the energy of motion
Heat
a measure of the total amount of kinetic energy due to molecular motion
Specific Heat
of a substance is the amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1^C
Specific heat of water
1 cal / g / ^C = amount of E to change temp
has a high specific heat, which allows it to minimize temperature fluctuations to within limits that permit life
Heat is absorbed when
hydrogen bonds break
Heat is released when
hydrogen bonds form
Evaporation
the transformation of a substance from a liquid to a gas
Heat of vaporization
the quantity of heat a liquid must absorb for 1g of it to be converted from a liquid to a gas
Evaporative cooling of water helps …
stabilize temperatures in organisms and bodies of water
Ice (solid water)
- less dense than liquid water and floats in liquid water
- it is more “ordered”
- becomes more rigid and forms a lattice
Water’s greatest density is at
4 degrees Celsius
Solvent of Life
universal solvent
Water
