Ap Biology (Campbell) Chapter 3: Water

Front 1

Polar molecule

Back 1

opposite ends of the molecule have opposite charges (one example is the water molecule

Front 2

Cohesion

Back 2

the phenomenon in which hydrogen bonds hold water together

Front 3

Adhesion

Back 3

the clinging of one substance to another

Front 4

Surface tension

Back 4

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

Front 5

What has kinetic energy?

Back 5

anything that moves

Front 6

What is heat a measure of?

Back 6

the total quantity of kinetic energy due to molecular motion in a body of water

Front 7

What does temperature measure?

Back 7

the intensity of heat due to the average kinetic energy of the molecules

Front 8

Calorie

Back 8

the amount of heat energy it takes to raise the temperature of 1 gram of water by one degree Celsius

Front 9

Kilocalorie

Back 9

the quantity of heat required to raise the temperature of 1 kilogram of water by one degree Celsius.

Front 10

Joule

Back 10

measurement of heat needed to raise the temperature of a unit of water0.239 calories, calorie= 4.184 J

Front 11

Specific heat

Back 11

the amount of heat that must be absorbed or lost for 1 gram of that substance to change its temperature by 1 degree C. can be thought of as how well an object resists changing its temperature. It changes a lot when it does change.

Front 12

Heat of vaporization

Back 12

the quantity of heat a liquid must absorb for one gram of it to be converted from eh liquid to gaseous state

Front 13

Evaporative cooling

Back 13

as a liquid evaporates the surface of the liquid that remains behind cools down

Front 14

Solution

Back 14

a liquid that is a completely homogeneous mixture of two or more substances

Front 15

Solvent

Back 15

the dissolving agent of a solution

Front 16

Solute

Back 16

the dissolved substance in a solution

Front 17

Aqueous solution

Back 17

a solution wherein water is the solvent

Front 18

Hydration shell

Back 18

sphere of water molecules around each dissolved ion

Front 19

Hydrophilic

Back 19

any substance, whether ionic or polar that has an affinity for water even if it does not dissolve

Front 20

Hydrophobic

Back 20

substances that are non-ionic and non-polar seem to repel water.

Front 21

Mole

Back 21

equal in number to the molecular weight of a substance but upscaled from Daltons to units of grams

Front 22

Molecular weight

Back 22

the sum of the weights of all the atoms in a molecule

Front 23

Molarity

Back 23

the number of moles of solute per liter of solution

Front 24

Hydrogen ion

Back 24

a single proton with a charge of +1 because the hydrogen bond shifts

Front 25

Hydroxide ion

Back 25

a water molecule that lost a proton when the hydrogen bond shifts. Has a charge of –1

Front 26

Acid

Back 26

a substance that increases the hydrogen ion concentration of a solution.

Front 27

Acidic solution

Back 27

when a solution has more H+ than OH-

Front 28

Base

Back 28

a substance that reduces the hydrogen ion concentration of a solution

Front 29

Basic solution

Back 29

when a solution has more OH- than H+

Front 30

Buffers

Back 30

substances that minimize changes in the concentration of H+ and OH- in a solutions

Front 31

Acidic precipitation

Back 31

rain, snow or fog that is more acidic than pH 5.6

Front 32

Between oxygen and hydrogen which is more electronegative?

Back 32

oxygen

Front 33

What happens because oxygen is more electronegative?

Back 33

oxygen has a slightly negative charge and hydrogen has a slightly positive charge

Front 34

How many hydrogen bonds can each water molecule make?

Back 34

4 bonds

Front 35

What is behind all of water’s special properties?

Back 35

hydrogen bonding

Front 36

Why does water have more structure than other liquids?

Back 36

hydrogen bonds are weak but they reform very quickly in liquid water

Front 37

What is an example of adhesion?

Back 37

water clings to vessels of a plant to help it move up to the leaves against gravity or a meniscus in a graduated cylinder

Front 38

What is an example of cohesion?

Back 38

molecules create a constant stream of water inside a plant to move it from the roots to the leaves.

Front 39

Why is there surface tension?

Back 39

at the surface between water and air, hydrogen bonds hold water molecules to each other and to the molecules below them. This makes the surface of water act like it has a special invisible coating.

Front 40

What is an example of surface tension?

Back 40

rock skipping, lizards walking on water

Front 41

What is an example of the difference between heat and temperature?

Back 41

a swimmer has higher temperature than the ocean but the ocean has more heat

Front 42

Is it hard to convert water from a liquid to a gas? Why?

Back 42

yes, because the many hydrogen bonds need to be broken in order for that to happen

Front 43

What are the three steps in the hydrogen bond cycle?

Back 43

1. hydrogen bonds are formed in water 2. they are broken by heat 3. they are reformed when the water cools again

Front 44

What is an example of the hydrogen bond cycle?

Back 44

when you boil water, you are adding heat to the water to break the bonds and change the water to steam. When you put your hands over the steam you feel heat and get wet as the bonds are reformed and the state changes back to water.

Front 45

How does water stabilize temperature?

Back 45

water absorbs heat from warmer air, and releases hat to cooler air. Ocean temperatures are stable for marine life. Organisms resist changes in their bodies due to high water content.