Chapter 3 - Water and Life Flashcards
Four important water properties to sustain life on Earth
- Cohesive Behavior
- Ability to moderate temperature
- Expansion upon freezing
- Versatility as a solvent
Hydrogen bonds
The bonds form, break, and re-form constantly with it’s neighbors (lasting a trillionths of second
Cohesion
Hydrogen bonds holding the substance (Water) together
Adhesion
Hydrogen bonds clinging to the molecules of cell walls (countering down pull of gravity)
Surface Tension
Measure of how difficult it is to stretch or break the surface of a liquid
How does water moderate air temperature
Absorbing heat from air that is warmer and releasing stored heat to air that is cooler
Kinetic energy
The energy of motion
Thermal energy
Kinetic energy with the random movement of atoms or molecules (related to temperature and depends on volume)
Temperature
Measure of energy that represents the average kinetic energy of the molecules in a body of matter, regardless of volume
Heat
Thermal energy in transfer from one body of matter to another
Calorie (cal)
Amount of heat it takes to raise the temperature of 1g of water by 1C
Specific heat
The amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1C
Heat of Vaporization
Quantity of heat a liquid must absorb for 1g of it to be converted from liquid to gas
Evaporative cooling
As liquid evaporates, the surface of the liquid that remains behind fools down
Hydration shell
Sphere of water molecules around each dissolved ion
