Campbell Biology Chapt 3

Front 1

Water

Back 1

The molecule that supports all life

Only common substance to exist in the natural environment in all three physical states

Waters emergent properties help sustain life due to the structure of the water molecule and allowing it to interact with other molecules

Front 2

Water molecule is what type of bond and why

Back 2

A polar covalent bond

Because oxygens electronegativity creates an uneven distribution of electrons

This polarity allows water molecules to form hydrogen bonds with each other

Front 3

Hydrogen bonds of water

Back 3

Last briefly

Continues to reform over and over

Due to polar covalent bonding: high electronegativity

Front 4

4 properties that facilitate an environment for life

Back 4

Cohesive behavior

Ability to moderate temperature

Expansion upon freezing

Versatility as a solvent

Front 5

Cohesion

Back 5

Hydrogen bonds holding together water molecules

Allows the transport of water against gravity

Picture a chain of molecules pulling each other up a tree. At the surface of the leaf, it evaporates

Front 6

Adhesion

Back 6

The attraction or clinging btw different substances

Ex btw water and plant cell walls allows water to travel up the tree defying gravity

Front 7

Surface tension

Back 7

Measure of the force needed to stretch or break the surface of a liquid

Related to cohesion

Water molecules have high surface tension. No bonding of water molecules above them on the surface. Bottom molecules pull downward. Creates a film

Front 8

Heat bank

Back 8

Absorbs or released with only a slight change in its own temperature

Water moderates air temp by absorbing heat and releasing cooler air

Front 9

Kinetic energy

Back 9

Energy or motion

Atoms and molecules moving

The faster they move the more, the more kinetic energy

Front 10

Thermal energy

Back 10

Random motion of atoms or molecules

Like shooting pool. One ball hits and releases energy

Front 11

Heat

Back 11

Thermal energy is transferred from one body of matter to another

Measure of total quantity of kinetic energy due to molecular motion in a body of matter

Think of ice in a drink. The ice absorbs thermal energy from the liquid

Front 12

Temperature

Back 12

Measure the intensity of heat in a body due to the avg kinetic energy of the molecules

As speed of molecules increases, temp increases

Breaking hydrogen bonds increases temperature

Heat is Measured by volume vs temp is measuring greater movement of molecules (boiling pot)

A swimming pool has more thermal energy bc of its volume

Front 13

When two objects of diff temps come together...

Back 13

Heat passes from the warmer to the cooler object

Ice cubes cool a glass by absorbing heat from the warmer liquid until they are the same temp

Front 14

Liquid vs freezing

Back 14

Higher kinetic energy in liquid held together by weak hydrogen bonds

Freezing hydrogen bonds are more stable allowing water molecules far apart

Front 15

A calorie

Back 15

The measurement of heat required to raise the temp of water 1g by 1degrees Celsius

It is also the amt of heat released when 1g of water releases when it cools by 1 degrees cel.

Front 16

Calories on food packages

Back 16

Actual kilocalories

1 kcal = 1,000 cal

Front 17

Joule

Back 17

Another unit of energy

1= .239 cal or 1 cal = 4.184

Front 18

Kilocalorie

Back 18

1000 cal

Quantity of heat required to raise the temp of 1 kilogram of water by 1 degree Celsius

Front 19

Specific heat

Back 19

Amount of heat that must be absorbed or lost for 1 g if that substance to change its temp by 1 degree Celsius

Water has a high specific heat

It resist changing its temp when it absorbs or release heat

Due to hydrogen bonding (hydrogen bonds keep reforming )

Front 20

Hydrogen bonds and heat

Back 20

Heat must be absorbed in order to break hydrogen bonds

Hydrogen bonds release a lot of heat when they are formed

1 cal of heat causes little change in temp of water bc much of that energy is used to disrupt hydrogen bonds and not speed up movement of water molecules

Front 21

Hydration shell

Back 21

Formed when water molecules surround the individual ions and dissolve them

Results in two solutes homogenously mixed

Due to water polarity

iE:salt dissolved in water.

Positive charge hydrogen attract negative anions and negative charge oxygen attract positive cations

Front 22

Water as a solvent

Back 22

Water is a good solvent bc it firms bonds w charged ionic compounds and hydrogen bonds with polar covalent molecules

Front 23

Heat of vaporization

Back 23

Heat a liquid must absorb for 1g to be converted to gas

Water has a high heat of vaporization: 580 cal to evaporate 1 g of water at room temp

Hydrogen bonds must break before water molecule can evaporate

Front 24

Hydrophobic substance

Back 24

Does not have an affinity for water

Nonionic and have nonpolar covalent bonds

Major ingredients of cell membranes

IE: oil molecules

Front 25

Solute in aqueous solutions

Back 25

Bio Chem is wet chemistry-most chems dissolve in water

Chem reactions depend on collisions of molecules n concentrations of solutes in aqueous solutions

Front 26

Molecular (mol) mass

Back 26

Sum of all masses of all atoms (atomic mass) in a molecule

Front 27

Mass of a mol

Back 27

Is equal to the avg mass of the compound in daltons

Front 28

Concentration

Back 28

# of solute molecules in a volume solution

Front 29

Specific heat

Back 29

Amount of heat that must be absorbed or lost for 1 g if that substance to change its temp by 1 degree Celsius

Water has a high specific heat

It resist changing its temp when it absorbs or release heat

Due to hydrogen bonding

Front 30

Avogadro number

Back 30

Number of molecules in 1 mole

6.02 x 10 to the 23rd

One mole of one substances has exactly the same number of molecules of any other substance

ie: 1 mole of sucrose =342g, 1 mole of NaCl=58.44g

Front 31

Molarity (M)

Back 31

Number of moles of solute per liter of solution= unit of concentration

Concentration of solute in solution

1 mole of a solution= 1 mole of substance dissolved in 1 liter of solvent

Front 32

Hydrogen bonds and heat

Back 32

Heat must be absorbed in order to break hydrogen bonds

Hydrogen bonds release a lot of heat when they are formed

1 cal of heat causes little change in temp of water bc much of that energy is used to distrust hydrogen bonds and not speed up movement of water molecules

Front 33

Heat of water and earth

Back 33

At night and during winter, water heats cooler air

Oceans and coastal lands are more stable than inland

Living things are made up of water so they can regulate temps better

Front 34

Evaporation/ vapor

Back 34

Transformation of liquid to gas

Molecules move faster and overcome attraction of other molecules

Front 35

Heat of vaporization

Back 35

Heat a liquid must absorb for 1g to be converted to gas

Water has a high heat of vaporization: 580 cal to evaporate 1 g at room temp

Hydrogen bonds must break before water molecule can evaporate

Front 36

Evaporative cooling

Back 36

As a liquid evaporates, it’s remaining surface cools

Stabilizes temps in organism and bodies of water

Most energetic molecules evaporate leaving lower kinetic molecules behind

Front 37

Floating of ice

Back 37

Water is less dense as a solid than as a liquid (ice is 10% less dense and it insulated water below) at 4 degrees Celsius

Water expand and more air in between=less denser

Each molecule bonded to 4 other molecules

Hydrogen bonds are more ordered allowing them to float

Front 38

Solution

Back 38

A liquid that is a completely homogeneous mixture of two or more substances (sugar cube in water)

Front 39

Solvent

Back 39

Dissolving agent

Water is a powerful solvent

Most chemical reactions in organisms involve solutes dissolved in water

Front 40

Capillary

Back 40

Involving cohesion and adhesion

Front 41

Reversible reaction

Back 41

The hydrogen ion

Drastically can change the concentrations of H+ and OH- which can affect a cell

Front 42

Acid and basic solutions

Back 42

Strong acids and bases dissociate completely in water ( HCL and NaOH

Weak acids and bases reversible release and accept back hydrogen bonds but still shift the balance

Front 43

Concentrations of H+ and OH-

Back 43

Con. Equal in water

Adding certain solutes (acids and bases) disrupts equilibrium changing the concentrations

Front 44

I mike of sucrose

Back 44

Back (Definition)

Front 45

Base

Back 45

Any substance that reduces the H+ concentration of a solution NaOH➡️Na+ + OH-

Front 46

pH

Back 46

Used to describe whether a solution is acidic or basic

pH = potential of hydrogen

Started 1909: German potenz meaning power of H

Front 47

Hydrogen ion

Back 47

A hydrogen atom in a hydrogen bond btw 2 water molecules can shift from one to the other (1 in 555 million)

Hydrogen leaves it’s electron behind and is transferred as a proton creating:

A hydrogen ion

A hydroxide ion

Front 48

pH unit

Back 48

7 is neutral

Solution of pH 3 is not twice as acidic as a solution of pH 6 but 1,000 times more acidic

Front 49

pH and body

Back 49

Most biological substances are around 6-8 except gastric which is 2 (to break hydrogen bonds)

If blood pH goes up or down, could kill organism

Front 50

Buffers

Back 50

pH regulatorssssss...mount up

Substances that minimize changes in concentrations of H+ and OH- in a solution

Most contain a weak acid and it’s corresponding base which combine reversibly with H+ ions

Front 51

Acid and basic solutions

Back 51

Strong acids and bases dissociate completely in water ( HCL and NaOH

Weak acids and bases reversible release and accept back hydrogen bonds but still shift the balance

Front 52

Carbonic acid

Back 52

Buffer Formed when CO2 reacts with water in blood plasma

Dissociates to yield a bicarbonate ion and a hydrogen ion

Front 53

Panting dog

Back 53

Water is evaporating from tongue

Front 54

Water is a versatile solvent

Back 54

Polar molecules

Front 55

I mike of sucrose

Back 55

Back (Definition)

Front 56

1 mole solutions (1M)

Back 56

Has 1 mole of a substance dissolved in 1 liter of a solvent

Contains 6.02^23 molecules

Has a mass equal to its mass # or molecular weight in g

Front 57

Why is it important to know one mole to make solutions

Back 57

If you dissolve 1 mole of NaCl which weights 58.44g in 1 liter you made a 1M salt solution

You can change this formula to make a 2 M solution by doubling the weight of salt

Front 58

Hydrogen ion

Back 58

A hydrogen atom in a hydrogen bond btw 2 water molecules can shift from one to the other (1 in 555 million)

Hydrogen leaves it’s electron behind and is transferred as a proton creating:

A hydrogen ion

A hydroxide ion

Front 59

Hydronium ion

Back 59

The molecule with the extra proton (H3O)

Represented as H+

Front 60

Hydroxide ion

Back 60

The molecule that lost the proton (OH-)

Front 61

7 elements that are molecules

Back 61

Diatomic

Hydrogen

Nitrogen

Oxygen

Fluorine

Chlorine

Bromine

Iodine

Front 62

O3

Back 62

Ozone

Allotrope of 02