Characteristics of Water as a Substance

Question 1

Water on Earth

Answer 1

70% of Earth’s Surface
3% Fresh Water
2% Frozen
1% Usable

Question 2

Density of Water

Answer 2

1000 grams/Liter

Question 3

Terrestrial Versus Aquatic

Answer 3

Terrestrial:
-Overcome gravity
-Distributed on limbs
-Flying must overcome air pressure
Aquatic:
-Overcome Water Pressure and Fluid Resistance
-Pressure makes breathing different
-Resistance is overcome by body
-Shape and surface texture

Question 4

Covalent Bonds

Answer 4

Atomic Bonds formed from sharing electrons

Question 5

Electronegativity

Answer 5

When an atom has magnetic attraction caused by the number of electrons in comparison to other atoms

Question 6

Hydrogen Bonds

Answer 6

Weaker bond caused by the polarity of the molecule. This gives water unique properties.

Question 7

Water Dissociation

Answer 7

When water molecules split into an H+ and an OH-

Question 8

Water acidity

Answer 8

Water with more H+

Question 9

Water basic

Answer 9

Water with more OH-

Question 10

pH

Answer 10

pH = -log(H+)

Question 11

Buffer Molecules

Answer 11

Molecules that help maintain a constant pH by binding or releasing H+

Question 12

pH of Aquatic Environments

Answer 12

0-2: Volcanic Lakes
2-6: Many Bog Lakes
7-10: Productive Hard Water Lakes
>10: Alkaline Desert Lakes

Question 13

Cohesion

Answer 13

The tendency of water molecules to stick together

This causes the viscosity of water

Question 14

Solvent

Answer 14

What is dissolving a material

Question 15

Solute

Answer 15

What is being dissolved

Question 16

Solution

Answer 16

Solvent and Solute combined

Question 17

Hydrophilic

Answer 17

“Water-loving”
Polar Solutes
ions

Question 18

Hydrophobic

Answer 18

“water-fearing”
Nonpolar Molecules
fats

Question 19

Specific Heat of Water

Answer 19

Water can absorb a lot of energy as heat before rising in temperature

Question 20

Composition of air

Answer 20

Nitrogen:78.6%
Oxygen: 20.9%
Water Vapor: 0.5%
Carbon Dioxide: 0.04%

Question 21

Dalton’s Gas Law

Answer 21

Partial Pressure: Individual gases in a mixture exert pressure proportional to their abundance

Question 22

Henry’s Gas Law

Answer 22

Diffusion between liquid and gases: amount of a gas in a solution is directly proportional to its partial pressure

Question 23

Gas Content

Answer 23

The actual amount of a gas in solution( at given partial pressure and temperature) Depends on the solubility of that gas in that particular liquid

Question 24

Solubility and Temperature Relation

Answer 24

Gases dissolve into liquid better when the liquid is cold

Colder water => More Oxygen

Question 25

Salinity

Answer 25

mg/L of ions in water

Measured in Specific Conductance or the conductivity of water

Question 26

Total Dissolved Solids (TDS)

Answer 26

Everything that is dissolved in water that can cause murkiness when in high quantities

Question 27

Hardness

Answer 27

The presence of heavier metals in solution in water

Question 28

Alkalinity

Answer 28

Acid Neutralizing Capacity (ANC)
Waters ability to absorb H+
This is a sign of an adequate buffering system

Question 29

Power of Moving Water

Answer 29

Power = (1/2) * Density of water * Velocity^3

Question 30

calorie

Answer 30

the amount of heat required to raise the temperature of one gram of water from 14.5 C to 15.5 C

Question 31

Heat and Water

Answer 31

Heat can cause a phase change in water
80 calories/g causes ice to melt
540 calories/g causes water to evaporate

Question 32

Diffusion

Answer 32

Random movement of molecules

Question 33

Laminar flow

Answer 33

Water moving as an entire unit

Question 34

Turbulent flow

Answer 34

High velocity and chaotic flow

Question 35

Eddies

Answer 35

circular turbulence

Question 36

Billows

Answer 36

turbulence between density layers in water

Question 37

Gyres

Answer 37

Large eddies (100m to km)