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LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Chapter 3
Water and Life
Lectures by
Erin Barley
Kathleen Fitzpatrick
© 2011 Pearson Education, Inc.
Overview: The Molecule That Supports
All of Life
• Water is the biological medium on Earth
• All living organisms require water more than any
other substance
• Most cells are surrounded by water, and cells
themselves are about 70–95% water
• The abundance of water is the main reason the
Earth is habitable
© 2011 Pearson Education, Inc.
Concept 3.2: Four emergent properties of
water contribute to Earth’s suitability for
life
• Four of water’s properties that facilitate an
environment for life are
– Cohesive behavior
– Ability to moderate temperature
– Expansion upon freezing
– Versatility as a solvent
© 2011 Pearson Education, Inc.
Cohesion of Water Molecules
• Collectively, hydrogen bonds hold water
molecules together, a phenomenon called
cohesion (Capillary action- the transport of water
against gravity in plants)
• Adhesion is an attraction between different
substances, for example, between water and
plant cell walls
© 2011 Pearson Education, Inc.
Animation: Water Transport
Right-click slide/select “Play”
© 2011 Pearson Education, Inc.
• Surface tension is a measure of how hard it is
to break the surface of a liquid
• Surface tension is related to cohesion
© 2011 Pearson Education, Inc.
Moderation of Temperature by Water
• Water absorbs heat from warmer air and
releases stored heat to cooler air
• Water can absorb or release a large amount of
heat with only a slight change in its own
temperature
• Ocean as climate moderator of Earth
© 2011 Pearson Education, Inc.
Heat and Temperature
• Kinetic energy is the energy of motion
• Heat is a measure of the total amount of kinetic
energy due to molecular motion
• Temperature measures the intensity of heat
due to the average kinetic energy of molecules
© 2011 Pearson Education, Inc.
• The Celsius scale is a measure of temperature
using Celsius degrees (°C)
• A calorie (cal) is the amount of heat required to
raise the temperature of 1 g of water by 1°C
• The “calories” on food packages are actually
kilocalories (kcal), where 1 kcal = 1,000 cal
• The joule (J) is another unit of energy where
1 J = 0.239 cal, or 1 cal = 4.184 J
© 2011 Pearson Education, Inc.
Water’s High Specific Heat
• The specific heat of a substance is the amount of
heat that must be absorbed or lost for 1 g of that
substance to change its temperature by 1ºC
• The specific heat of water is 1 cal/g/ºC
• Water resists changing its temperature because of
its high specific heat
© 2011 Pearson Education, Inc.
• Water’s high specific heat can be traced to
hydrogen bonding
– Heat is absorbed when hydrogen bonds break
– Heat is released when hydrogen bonds form
• The high specific heat of water minimizes
temperature fluctuations to within limits that
permit life
© 2011 Pearson Education, Inc.
Figure 3.5
Los Angeles
(Airport) 75°
70s (°F)
80s
San Bernardino
100°
Riverside 96°
Santa Ana
Palm Springs
84°
106°
Burbank
90°
Santa Barbara 73°
Pacific Ocean 68°
90s
100s
San Diego 72°
40 miles
Evaporative Cooling
• Evaporation is transformation of a substance from
liquid to gas
• Heat of vaporization is the heat a liquid must
absorb for 1 g to be converted to gas
• As a liquid evaporates, its remaining surface
cools, a process called evaporative cooling
• Evaporative cooling of water helps stabilize
temperatures in organisms and bodies of water
© 2011 Pearson Education, Inc.
Floating of Ice on Liquid Water
• Ice floats in liquid water because hydrogen bonds
in ice are more “ordered,” making ice less dense
• Water reaches its greatest density at 4°C
• If ice sank, all bodies of water would eventually
freeze solid, making life impossible on Earth
© 2011 Pearson Education, Inc.
Figure 3.6
Hydrogen bond
Ice:
Hydrogen bonds
are stable
Liquid water:
Hydrogen bonds
break and re-form
Water: The Solvent of Life
• A solution is a liquid that is a homogeneous
mixture of substances
• A solvent is the dissolving agent of a solution
• The solute is the substance that is dissolved
• An aqueous solution is one in which water is
the solvent
• Coffee and sugar
© 2011 Pearson Education, Inc.
• Water can also dissolve compounds made of
nonionic polar molecules
• Even large polar molecules such as proteins
can dissolve in water if they have ionic and
polar regions
© 2011 Pearson Education, Inc.
Hydrophilic and Hydrophobic Substances
• A hydrophilic substance is one that has an
affinity for water
• A hydrophobic substance is one that does not
have an affinity for water
• Oil molecules are hydrophobic because they
have relatively nonpolar bonds
• A colloid is a stable suspension of fine particles
in a liquid
© 2011 Pearson Education, Inc.
Solute Concentration in Aqueous Solutions
• Most biochemical reactions occur in water
• Chemical reactions depend on collisions of
molecules and therefore on the concentration of
solutes in an aqueous solution
© 2011 Pearson Education, Inc.
Concept 3.3: Acidic and basic conditions
affect living organisms
• A hydrogen atom in a hydrogen bond between
two water molecules can shift from one to the
other
– The hydrogen atom leaves its electron behind
and is transferred as a proton, or hydrogen
ion (H+)
– The molecule with the extra proton is now a
hydronium ion (H3O+), though it is often
represented as H+
– The molecule that lost the proton is now a
hydroxide ion (OH–)
© 2011 Pearson Education, Inc.
Figure 3.UN02
+
2 H 2O
Hydronium
ion (H3O+)

Hydroxide
ion (OH)
• Though statistically rare, the dissociation of
water molecules has a great effect on
organisms
• Changes in concentrations of H+ and
OH– can drastically affect the
chemistry of a cell
© 2011 Pearson Education, Inc.
• Concentrations of H+ and OH– are equal in pure
water
• Adding certain solutes, called acids and bases,
modifies the concentrations of H+ and OH–
• Biologists use something called the pH scale to
describe whether a solution is acidic or basic
(the opposite of acidic)
© 2011 Pearson Education, Inc.
Acids and Bases
• An acid is any substance that increases the H+
concentration of a solution
• A base is any substance that reduces the H+
concentration of a solution
© 2011 Pearson Education, Inc.
The pH Scale
• In any aqueous solution at 25°C the product of
H+ and OH– is constant and can be written as
[H+][OH–] = 10–14
• The pH of a solution is defined by the negative
logarithm of H+ concentration, written as
pH = –log [H+]
• For a neutral aqueous solution, [H+] is 10–7, so
pH = –(–7) = 7
© 2011 Pearson Education, Inc.
Figure 3.10
H+
H+
 H+
H+ OH
+

OH H H+
+
H H+
Acidic
solution
Increasingly Acidic
[H+] > [OH]
pH Scale
0
1
Battery acid
2
Gastric juice, lemon juice
3
Vinegar, wine,
cola
4
Tomato juice
Beer
Black coffee
5
6
Neutral
solution
OH
OH
OH H+ OH

OH OH
OH
+
H
Basic
solution
Neutral
[H+] = [OH]
7
8
Increasingly Basic
[H+] < [OH]
OH
OH
H+ H+ OH

OH OH +
H+ H+ H
Rainwater
Urine
Saliva
Pure water
Human blood, tears
Seawater
Inside of small intestine
9
10
Milk of magnesia
11
Household ammonia
12
13
Household
bleach
Oven cleaner
14
Buffers
• The internal pH of most living cells must remain
close to pH 7
• Buffers are substances that minimize changes
in concentrations of H+ and OH– in a solution
• Most buffers consist of an acid-base pair that
reversibly combines with H+
© 2011 Pearson Education, Inc.
Acidification: A Threat to Water Quality
• Human activities such as burning fossil fuels
threaten water quality
• CO2 is the main product of fossil fuel combustion
• About 25% of human-generated CO2 is
absorbed by the oceans
• CO2 dissolved in sea water forms carbonic acid;
this process is called ocean acidification
© 2011 Pearson Education, Inc.
Figure 3.11
CO2
CO2 + H2O
H2CO3
H2CO3
H+ + HCO3
H+ + CO32
CO32 + Ca2+
HCO3
CaCO3
• As seawater acidifies, H+ ions combine with
carbonate ions to produce bicarbonate
• Carbonate is required for calcification
(production of calcium carbonate) by many
marine organisms, including reef-building
corals
© 2011 Pearson Education, Inc.
• The burning of fossil fuels is also a major source
of sulfur oxides and nitrogen oxides
• These compounds react with water in the air to
form strong acids that fall in rain or snow
• Acid precipitation is rain, fog, or snow with a pH
lower than 5.2
• Acid precipitation damages life in lakes and
streams and changes soil chemistry on land
© 2011 Pearson Education, Inc.
LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Chapter 3
Water and Life
Questions prepared by
Ruth Buskirk
University of Texas at Austin
Lectures
by
Jung Choi
Erin
Barley
Georgia Institute
of Technology
Kathleen Fitzpatrick
© 2011 Pearson Education, Inc.
The four emergent properties of water
that are important for life are:
a) Cohesion, expansion upon freezing, high heat of
evaporation, and capillarity
b) Cohesion, moderation of temperature, expansion
upon freezing, and solvent properties
c) Moderation of temperature, solvent properties, high
surface tension, and capillarity
d) Heat of vaporization, high specific heat, high
surface tension, and capillarity
e) Polarity, hydrogen bonding, high specific heat, and
high surface tension
The four emergent properties of water
that are important for life are:
a) Cohesion, expansion upon freezing, high heat of
evaporation, and capillarity
b) Cohesion, moderation of temperature, expansion
upon freezing, and solvent properties
c) Moderation of temperature, solvent properties, high
surface tension, and capillarity
d) Heat of vaporization, high specific heat, high
surface tension, and capillarity
e) Polarity, hydrogen bonding, high specific heat, and
high surface tension
Water has an unusually high specific
heat. This is directly related to which one
of the following?
– At its boiling point, water changes from liquid to
vapor.
– More heat is required to raise the temperature of
water.
– Ice floats in liquid water.
– Salt water freezes at a lower temperature than pure
water.
– Floating ice can insulate bodies of water.
Water has an unusually high specific
heat. This is directly related to which one
of the following?
– At its boiling point, water changes from liquid to
vapor.
– More heat is required to raise the temperature of
water.
– Ice floats in liquid water.
– Salt water freezes at a lower temperature than pure
water.
– Floating ice can insulate bodies of water.
Surfactants reduce surface tension of a
liquid. Which of the following would
result if water was treated with
surfactants?
a) Surfactant-treated water droplets will form a thin
film instead of beading on a waxed surface.
b) Surfactant-treated water will form smaller droplets
when dripping from a sink.
c) Water striders will sink.
d) All of the above will occur
e) Only a and c will occur.
Surfactants reduce surface tension of a
liquid. Which of the following would
result if water was treated with
surfactants?
a) Surfactant-treated water droplets will form a thin
film instead of beading on a waxed surface.
b) Surfactant-treated water will form smaller droplets
when dripping from a sink.
c) Water striders will sink.
d) All of the above will occur
e) Only a and c will occur.
A calorie is defined as:
a) The amount of energy required to raise the
temperature of 1 gram of water by 1 degree F.
b) The amount of energy required to raise the
temperature of 1 gram of water by 1 degree C.
c) The amount of energy released by metabolism of
one gram of glucose.
d) The amount of energy contained in one gram of
fat.
e) The amount of energy required to raise the
temperature of 1 liter of water by 1 degree C.
A calorie is defined as:
a) The amount of energy required to raise the
temperature of 1 gram of water by 1 degree F.
b) The amount of energy required to raise the
temperature of 1 gram of water by 1 degree C.
c) The amount of energy released by metabolism of
one gram of glucose.
d) The amount of energy contained in one gram of
fat.
e) The amount of energy required to raise the
temperature of 1 liter of water by 1 degree C.
In humans, blood pH is around 7.4, and a
decrease in blood pH to 6.4 would be fatal. A
drop by 1 pH unit represents which of these?
a)
b)
c)
d)
e)
1/10 as many H+ ions in the solution
1/7 as many H+ ions in the solution
1/2 as many H+ ions in the solution
twice as many H+ ions in the solution
ten times as many H+ ions in the solution
In humans, blood pH is around 7.4, and a
decrease in blood pH to 6.4 would be fatal. A
drop by 1 pH unit represents which of these?
a)
b)
c)
d)
e)
1/10 as many H+ ions in the solution
1/7 as many H+ ions in the solution
1/2 as many H+ ions in the solution
twice as many H+ ions in the solution
ten times as many H+ ions in the solution
The chemical equilibrium between carbonic acid and
bicarbonate acts as a pH regulator in our blood. If the
blood pH begins to rise, what will happen?
H2CO3
↔
HCO3–
+
H+
Carbonic acid
Bicarbonate ion
Hydrogen ion
a) reaction proceeds to the right; more carbonic acid
dissociates
b) reaction proceeds to the right; more carbonic acid
forms
c) reaction proceeds to the left; more carbonic acid
dissociates
d) reaction proceeds to the left; more carbonic acid forms
The chemical equilibrium between carbonic acid and
bicarbonate acts as a pH regulator in our blood. If the
blood pH begins to rise, what will happen?
H2CO3
↔
HCO3–
+
H+
Carbonic acid
Bicarbonate ion
Hydrogen ion
a) reaction proceeds to the right; more carbonic acid
dissociates
b) reaction proceeds to the right; more carbonic acid
forms
c) reaction proceeds to the left; more carbonic acid
dissociates
d) reaction proceeds to the left; more carbonic acid forms
Scientists are concerned about increased
concentrations of atmospheric carbon dioxide due to
increased fossil fuel combustion and deforestation. In
addition to major effects on global temperatures,
increased levels of CO2 can threaten aquatic organisms
in which way?
a) forming more carbonic acid in a solution that raises the pH
of seawater
b) forming more carbonic acid that decreases the
concentration of carbonate ions in seawater
c) increasing photosynthesis rates in aquatic plants and algae
d) decreasing the oxygen available for cellular respiration in
aquatic organisms
e) increasing the levels of harmful sulfur oxides and nitrous
oxides
Scientists are concerned about increased
concentrations of atmospheric carbon dioxide due to
increased fossil fuel combustion and deforestation. In
addition to major effects on global temperatures,
increased levels of CO2 can threaten aquatic organisms
in which way?
a) forming more carbonic acid in a solution that raises the pH
of seawater
b) forming more carbonic acid that decreases the
concentration of carbonate ions in seawater
c) increasing photosynthesis rates in aquatic plants and algae
d) decreasing the oxygen available for cellular respiration in
aquatic organisms
e) increasing the levels of harmful sulfur oxides and nitrous
oxides
LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Chapter 4
Carbon and the Molecular
Diversity of Life
Lectures by
Erin Barley
Kathleen Fitzpatrick
© 2011 Pearson Education, Inc.
Overview: Carbon: The Backbone of Life
• Living organisms consist mostly of carbon-based
compounds (ORGANIC)
• Organic chemistry is the study of compounds
that contain carbon
• Organic compounds range from simple molecules
to colossal ones
• Most organic compounds contain hydrogen atoms
in addition to carbon atoms
© 2011 Pearson Education, Inc.
• Vitalism, the idea that organic compounds
arise only in organisms, was disproved when
chemists synthesized these compounds
• Mechanism is the view that all natural
phenomena are governed by physical and
chemical laws
© 2011 Pearson Education, Inc.
Organic Molecules and the Origin of Life
on Earth
• Stanley Miller’s classic experiment
demonstrated the abiotic synthesis of
organic compounds
• Experiments support the idea that abiotic
synthesis of organic compounds, perhaps
near volcanoes, could have been a stage in
the origin of life
© 2011 Pearson Education, Inc.
Figure 4.2
EXPERIMENT
“Atmosphere”
CH4
Water vapor
Electrode
Condenser
Cooled “rain”
containing
organic
molecules
H2O
“sea”
Sample for chemical analysis
Cold
water
Concept 4.2: Carbon atoms can form diverse
molecules by bonding to four other atoms
• Electron configuration is the key to an atom’s
characteristics
• Electron configuration determines the kinds
and number of bonds an atom will form with
other atoms
© 2011 Pearson Education, Inc.
The Formation of Bonds with Carbon
• With four valence electrons, carbon can form
four covalent bonds with a variety of atoms 
ability makes large, complex molecules
• In molecules with multiple carbons, each carbon
bonded to four other atoms has a tetrahedral
shape
• However, when two carbon atoms are joined by
a double bond, the atoms joined to the carbons
are in the same plane as the carbons
© 2011 Pearson Education, Inc.
Figure 4.3
Name and
Comment
Molecular
Formula
(a) Methane
CH4
(b) Ethane
C2H6
(c) Ethene
(ethylene)
C2H4
Structural
Formula
Ball-andStick Model
Space-Filling
Model
Figure 4.4
Hydrogen
(valence  1)
Oxygen
(valence  2)
Nitrogen
(valence  3)
Carbon
(valence  4)
Figure 4.5
(c) Double bond position
(a) Length
Ethane
Propane
(b) Branching
Butane
1-Butene
2-Butene
(d) Presence of rings
2-Methylpropane
(isobutane)
Cyclohexane
Benzene
Hydrocarbons
• Hydrocarbons are organic molecules
consisting of only carbon and hydrogen
• Many organic molecules, such as fats, have
hydrocarbon components
• Hydrocarbons can undergo reactions that
release a large amount of energy
© 2011 Pearson Education, Inc.
Figure 4.6
Nucleus
Fat droplets
10 m
(a) Part of a human adipose cell
(b) A fat molecule
Isomers
• Isomers are compounds with the same
molecular formula but different structures and
properties
– Structural isomers have different covalent
arrangements of their atoms
– Cis-trans isomers have the same covalent
bonds but differ in spatial arrangements
– Enantiomers are isomers that are mirror
images of each other
© 2011 Pearson Education, Inc.
Animation: Isomers
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
Figure 4.7
(a) Structural isomers
(b) Cis-trans isomers
cis isomer: The two Xs
are on the same side.
trans isomer: The two Xs
are on opposite sides.
(c) Enantiomers
CO2H
CO2H
H
NH2
CH3
L isomer
NH2
H
CH3
D isomer
• Enantiomers are important in the
pharmaceutical industry- Dopamine
• Two enantiomers of a drug may have different
effects
• Usually only one isomer is biologically active
• Differing effects of enantiomers demonstrate
that organisms are sensitive to even subtle
variations in molecules
© 2011 Pearson Education, Inc.
Animation: L-Dopa
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
Figure 4.8
Drug
Condition
Ibuprofen
Pain;
inflammation
Albuterol
Effective
Enantiomer
Ineffective
Enantiomer
S-Ibuprofen
R-Ibuprofen
R-Albuterol
S-Albuterol
Asthma
Concept 4.3: A few chemical groups are key
to the functioning of biological molecules
• Distinctive properties of organic
molecules depend on the carbon
skeleton and on the molecular
components attached to it
• A number of characteristic groups can
replace the hydrogens attached to skeletons
of organic molecules
© 2011 Pearson Education, Inc.
The Chemical Groups Most Important in
the Processes of Life
• Functional groups are the components of
organic molecules that are most commonly
involved in chemical reactions
• The number and arrangement of functional
groups give each molecule its unique
properties
© 2011 Pearson Education, Inc.
Figure 4.UN02
Estradiol
Testosterone
• The seven functional groups that are most
important in the chemistry of life:
–
–
–
–
–
–
–
Hydroxyl group
Carbonyl group
Carboxyl group
Amino group
Sulfhydryl group
Phosphate group
Methyl group
© 2011 Pearson Education, Inc.
Figure 4.9-a
CHEMICAL
GROUP
Hydroxyl
Carbonyl
Carboxyl
STRUCTURE
(may be written HO—)
NAME OF
COMPOUND
Alcohols (Their specific names
usually end in -ol.)
Ketones if the carbonyl group is
within a carbon skeleton
Carboxylic acids, or organic acids
Aldehydes if the carbonyl group
is at the end of the carbon skeleton
EXAMPLE
Ethanol
Acetone
Acetic acid
Propanal
FUNCTIONAL
PROPERTIES
• Is polar as a result of the
electrons spending more time
near the electronegative oxygen
atom.
• Can form hydrogen bonds with
water molecules, helping dissolve
organic compounds such as
sugars.
• A ketone and an aldehyde may be
structural isomers with different
properties, as is the case for
acetone and propanal.
• Ketone and aldehyde groups are
also found in sugars, giving rise
to two major groups of sugars:
ketoses (containing ketone
groups) and aldoses (containing
aldehyde groups).
• Acts as an acid; can donate an
H+ because the covalent bond
between oxygen and hydrogen
is so polar:
Nonionized
Ionized
• Found in cells in the ionized form
with a charge of 1 and called a
carboxylate ion.
Figure 4.9-b
Amino
Sulfhydryl
Phosphate
Methyl
(may be
written HS—)
Amines
Organic phosphates
Thiols
Cysteine
Glycine
• Acts as a base; can
pick up an H+ from the
surrounding solution
(water, in living
organisms):
Nonionized
Ionized
• Found in cells in the
ionized form with a
charge of 1+.
Glycerol phosphate
• Two sulfhydryl groups can
react, forming a covalent
bond. This “cross-linking”
helps stabilize protein
structure.
• Contributes negative charge to
the molecule of which it is a part
(2– when at the end of a molecule,
as above; 1– when located
internally in a chain of
phosphates).
• Cross-linking of cysteines
in hair proteins maintains
the curliness or straightness
of hair. Straight hair can be
“permanently” curled by
shaping it around curlers
and then breaking and
re-forming the cross-linking
bonds.
• Molecules containing phosphate
groups have the potential to react
with water, releasing energy.
Methylated compounds
5-Methyl cytidine
• Addition of a methyl group
to DNA, or to molecules
bound to DNA, affects the
expression of genes.
• Arrangement of methyl
groups in male and female
sex hormones affects their
shape and function.
ATP: An Important Source of Energy for
Cellular Processes
• One phosphate molecule, adenosine
triphosphate (ATP), is the primary energytransferring molecule in the cell
• ATP consists of an organic molecule called
adenosine attached to a string of three
phosphate groups
© 2011 Pearson Education, Inc.
Figure 4. UN04
Adenosine
Figure 4. UN05
Reacts
with H2O
Adenosine
Adenosine
ATP
Inorganic
phosphate
ADP
Energy
The Chemical Elements of Life: A Review
• The versatility of carbon makes possible the
great diversity of organic molecules
• Variation at the molecular level lies at the
foundation of all biological diversity
© 2011 Pearson Education, Inc.
LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Chapter 4
Carbon and the Molecular
Diversity of Life
Questions prepared by
William Wischusen
Louisiana State University
Lectures
by
Jung Choi
Erin
Barley
Georgia Institute
of Technology
Kathleen Fitzpatrick
© 2011 Pearson Education, Inc.
What functional group is commonly used
in cells to transfer energy from one
organic molecule to another?
•a) carboxyl
•b) sulfhydryl
•c) hydroxyl
•d) phosphate
•e) amino
What functional group is commonly used
in cells to transfer energy from one
organic molecule to another?
•a) carboxyl
•b) sulfhydryl
•c) hydroxyl
•d) phosphate
•e) amino
The Miller-Urey experiment, shown
below,
a) showed that the conditions of
early Earth were inhospitable
to life
b) demonstrated that amino
acids and other organic
molecules form under
conditions that may have
existed on Earth before life
began
c) proved that life could originate
from inorganic chemicals
d) both B and C
The Miller-Urey experiment, shown
below,
a) showed that the conditions of
early Earth were inhospitable
to life
b) demonstrated that amino
acids and other organic
molecules form under
conditions that may have
existed on Earth before life
began
c) proved that life could originate
from inorganic chemicals
d) both B and C
Based on carbon’s valence (4), how many
different molecular shapes can be made
from 6 carbons?
–
–
–
–
–
1
2
4
6
more than 6
Based on carbon’s valence (4), how many
different molecular shapes can be made
from 6 carbons?
–
–
–
–
–
1
2
4
6
more than 6
Given a chemical formula for an organic
molecule, (e.g., C6H12O6), one can
usually deduce its
a)
b)
c)
d)
e)
Structure
Molecular weight
Solubility in water
All of the above
Molecular weight and solubility in water
Given a chemical formula for an organic
molecule, (e.g., C6H12O6), one can
usually deduce its
a)
b)
c)
d)
e)
Structure
Molecular weight
Solubility in water
All of the above
Molecular weight and solubility in water
Is this molecule soluble in water?
– yes
– no
Is this molecule soluble in water?
– yes
– no
Compared to a carbon atom with only
single covalent bonds, a carbon with a
double bond
a) Shares fewer electron pairs with other atoms
b) Is more flexible in the spatial arrangement of its
bonds
c) Has a planar configuration of its electron orbitals
rather than a tetrahedral configuration
d) Is more polar
Compared to a carbon atom with only
single covalent bonds, a carbon with a
double bond
a) Shares fewer electron pairs with other atoms
b) Is more flexible in the spatial arrangement of its
bonds
c) Has a planar configuration of its electron orbitals
rather than a tetrahedral configuration
d) Is more polar
The general structure of amino acids are
shown in this figure. What functional
groups are highlighted in salmon and
yellow, respectively?
a) Amino and carboxyl
b) Amino and carbonyl
c) Hydroxyl and
carbonyl
d) Methyl and carboxyl
e) Methyl and hydroxyl
The general structure of amino acids are
shown in this figure. What functional
groups are highlighted in salmon and
yellow, respectively?
a) Amino and carboxyl
b) Amino and carbonyl
c) Hydroxyl and
carbonyl
d) Methyl and carboxyl
e) Methyl and hydroxyl