Biology 1 Chapter 3 (Lecture)

Question 1

What is the only common substance to exist in the natural environment that exist in all 3 physical states of matter?

Answer 1

Water

Question 2

What is the major reason Earth is inhabitable?

Answer 2

Abundance of water.

Question 3

Cells are ____ water?

Answer 3

70-95%

Question 4

What does it mean that water is a polar molecule?

Answer 4

The 2 ends of the molecule have opposite charges; oxygen region has partial negative, and the hydrogen regions have partial positive.

Question 5

Hydrogen Bonds

Answer 5

Bond between water molecules

Question 6

IMPORTANT QUALITY OF WATER

Answer 6

The H bonds are fragile & are breaking and reforming.

Question 7

Ability to moderate ______ due to having high specific heat and evaporative cooling

Answer 7

Temperature.

Question 8

Water expands upon

Answer 8

Freezing

Question 9

Water is a

Answer 9

Solvent

Question 10

Heat

Answer 10

Total kinetic energy due to motion of its molecules

Question 11

Temperature

Answer 11

Measure of heat intensity that represents the average kinetic energy of the molecules.

Question 12

Ice Cube

Answer 12

Not by adding cold by absorbing heat.

Question 13

Water Freezes

Answer 13

0 C

Question 14

Water Boils

Answer 14

100 C

Question 15

Human Body

Answer 15

37 C

Question 16

Room Temp

Answer 16

20-25 C

Question 17

Why does evaporative cooling occur?

Answer 17

as a liquid evaporates the surface of the liquid that remains behind cools down. (Stability of temp)

Question 18

When water freezes

Answer 18

is less dense (ice floats, forming a barrier in lakes and ponds)

Question 19

The dissociation of water yields the __ ion and the __ ion

Answer 19

H+ and OH-

Question 20

pH scale

Answer 20

Describes how acidic and basic a solution is. (0-14)

Question 21

The product of the [H+] times the [OH-] is

Answer 21

10 ^ -14

Question 22

Neutral Solution

Answer 22

10^-7

Question 23

pH=

Answer 23

-log[H+]

Question 24

Substances that minimize changes in the concentrations of H+ ions and OH- ions.

Answer 24

Buffers

Question 25

Acid

Answer 25

A substance that increases the H+ concentration of a solution; pH below 7

Question 26

Solvent

Answer 26

The dissolving agent of a solution

Question 27

Solute

Answer 27

The substance that is dissolved in a solution

Question 28

Mole

Answer 28

The amount of mass of a substance that contains 6.023 X 10^23 molecules of that substance.

Question 29

Polar Molecule

Answer 29

Molecule that has an uneven distribution of charges

Question 30

Surface Tension

Answer 30

Measure of how difficult it is to stretch or break the surface of a liquid

Question 31

Cohesion

Answer 31

Attraction of water molecules to other water molecules and held by hydrogen bonds.

Question 32

Specific Heat

Answer 32

Amount of heat that must be absorbed or lost to change the temp of 1 gram of a substance 1 degree C

Question 33

Hydrophilic

Answer 33

Substance that has an affinity for water

Question 34

Hydrophobic

Answer 34

Substance that repels water

Question 35

Adhesion

Answer 35

Attraction between different substances

Question 36

Occur because of a change of the molecules with greatest kinetic energy changing from liquid to gas

Answer 36

Evaporative Cooling

Question 37

pH of blood

Answer 37

7.4

Question 38

Property of water that tends to stabilize the ocean temp.

Answer 38

High Specific Heat

Question 39

Property of water that helps to moderate earth’s climate

Answer 39

High Heat of Vaporization

Question 40

Determines the cohesiveness of water molecules

Answer 40

Hydrogen bonds.