IB 150 Final
Exam
Review
, UNIT k: LI/E 4ND ENE4GY
]ggk 1 Lga¥níng GoaCg
TSg gng¥gg3ícg o/ Cí/g
1. Understand how to use a manipulative experiment to answer
questions with the scientific method.
BASIC SHIT
A. Define and be able to write a hypothesis as a statement that reflects a potential
explanation for the research question.
B. Use deductive logic to derive unique, testable predictions to a hypothesis.
C. Differentiate between independent and dependent variables, and use them
appropriately to set up predictions of concrete results you would expect, if the
hypothesis is correct.
D. Graph qualitatively the predicted data, identifying which treatments are
expected to differ significantly (more than expected due to chance alone).
E. Set-up an appropriate experiment that controls for the independent variable and
minimizes the effect of other environmental variables, and includes a control
treatment and replication in its design.
F. Identify the role and utility of control treatments, replication of treatments, and
sample size in any experiment.
2. What does it mean to be alive?
A. List the five characteristics all organisms on Earth share.
1) Energy - Organisms must acquire and use energy to stay alive and reproduce. E.g.
plants absorb sunlight; animals ingest food
2) Cells - Organisms are made of membrane-bound units called cells. Cells regulate the
passage of materials between exterior and interior spaces.
3) Information - Organisms process hereditary (genetic) information encoded in units
called genes. Organisms also respond to information from the environment + adjust
to maintain stable internal conditions.
4) Replication - Almost everything an organism does contributes to one goal: replacing itself
5) Evolution - Organisms are the product of evolution, and their populations continue to
evolve.
B. Explain why the first four are required for life.
1) Organisms require energy to stay alive and reproduce.
2) All organisms are made of cells.
3) The chemical reactions that sustain life take place inside the cells.
4) Cells contain genetic information that encodes for an organism to be alive.
5) Organisms also must respond to information from the environment and adjust
to maintain homeostasis.
,6) Cells must replicate during meiosis (sexual reproduction) to ensure that all
organisms contain the correct number of chromosomes.
C. Understand how the ability to perform work is related to being alive.
Anabolic and Catabolic reactions allow for all of the processes in our cells to occur.
Without work occurring within our bodies, we are unable to function (move, sleep,
eat, breathe)
D. Predict the direction of net flow of water across a cell membrane due to
osmosis given information about solute concentrations on either side of the
membrane. Explain what happens to rates of movement of water molecules in
both directions across the membrane at equilibrium.
Water flows into cells because there is higher concentration of salt inside a cell. So,
it moves from high to low concentration. When an equilibrium is met there is no
net movement of molecules, however, molecules are still moving randomly.
E. Understand that net flow of molecules due to osmosis is a result of the rates of
movement of particles in both directions, NOT as a result of an inherent
preference or force moving these molecules in one direction or the other.
Particles move randomly from bouncing off of each other, if there is a higher
concentration then particles will bounce off of each other more frequently and this
results in a desire to reach equilibrium
3.Be able to apply the First and Second Law of Thermodynamics
and explain their relevance to living processes
A. Define the First and Second Law of Thermodynamics.
1) First Law of Thermodynamics - Energy is conserved, it cannot be created or
destroyed, but only transferred and transformed
2) Second Law of Thermodynamics - entropy always increases in an isolated system
B. Use the First Law of Thermodynamics to explain how chemical reactions transfer
energy from one molecule to another.
1) Energy changes from one form to another (potential, kinetic).
2) Stored energy is called potential energy. An object gains or loses its
ability to store energy because of its position. Potential energy can be
converted to motion.
3) Kinetic energy is the energy of motion. Molecules have kinetic energy
because they are constantly in motion.
Thermal energy (heat)
Potential energy is stored in the bonds
When a reaction is endothermic it has to have energy put in
it When a reaction is exothermic is releases energy
C. Understand how molecules store chemical potential energy.
1) Associated with electrons in atoms
2) Most stable situation - negatively charged electron is very close to the
positively charged nucleus of an atom.
3) Further the electron is moved from the nucleus, the more chemical
potential energy it has.
4) More potential to convert this potential energy into kinetic energy and move
towards the nucleus (if given the chance)
5) Chemical energy is the energy involved in chemical reactions - elements
join together into compounds
6) Energy is stored inside the compounds as chemical potential energy
, 7) Energy can be released by further chemical reactions
8) When bonds are broken, potential energy is released
9) Two elements form a chemical bond, they share electrons
10) Element with higher electronegativity (ability to attract electrons)
grabs the shared electron more closely to its nucleus than the other
element
D. Determine whether a change of a system increases or decreases in
enthalpy (ΔH) and entropy (ΔS) over the course of the reaction.
1) In general, physical and chemical processes proceed in the direction
that results in increased entropy and lower potential energy
2) Spontaneous Reaction - products have lower potential energy than the
reactants (electrons in products are held more tightly than those in
the reactants)
3) Reaction wants to move in a direction that REDUCES the total internal
energy of the system
4) A reaction is favorable if entropy increases
5) Entropy (ΔS) - dispersal of energy and matter (disorder)
6) A reaction is favorable if enthalpy decreases (releases heat)
Enthalpy (ΔH) - amount of heat released or absorbed by a chemical reaction
E. Use the Second Law of Thermodynamics to predict whether a process is
exergonic or endergonic and thus will proceed spontaneously or not by
qualitatively applying the equation ΔG = ΔH – T*ΔS.
1) Gibbs Free Energy Equation
2) Change in Gibbs Free Energy = change in potential energy of the
system/change in the disorder of the system
3) When ΔG decreases, means energy is released and the reaction is spontaneous
4) Negative enthalpy (ΔH) reaction is spontaneous
5) Positive entropy (ΔS) reaction is spontaneous
6) Not all spontaneous reactions are exergonic
F. Define exergonic and endergonic chemical reactions.
1) Exergonic Reactions
Release energy (can be used to do work)
Tend to be spontaneous
Reactants have a higher Gibbs Free Energy than the
products ΔH (Enthalpy) is negative (heat given off)
ΔS (Entropy) is positive
2) Endergonic Reactions
Requires energy to be done on the system for the reaction to
proceed qΔH (Enthalpy) is positive (heat absorbed)
4. How do organisms control exergonic reaction rates?
A. Be able to draw a graph that illustrates activation energy in a graph of
the time course of a chemical reaction
Exam
Review
, UNIT k: LI/E 4ND ENE4GY
]ggk 1 Lga¥níng GoaCg
TSg gng¥gg3ícg o/ Cí/g
1. Understand how to use a manipulative experiment to answer
questions with the scientific method.
BASIC SHIT
A. Define and be able to write a hypothesis as a statement that reflects a potential
explanation for the research question.
B. Use deductive logic to derive unique, testable predictions to a hypothesis.
C. Differentiate between independent and dependent variables, and use them
appropriately to set up predictions of concrete results you would expect, if the
hypothesis is correct.
D. Graph qualitatively the predicted data, identifying which treatments are
expected to differ significantly (more than expected due to chance alone).
E. Set-up an appropriate experiment that controls for the independent variable and
minimizes the effect of other environmental variables, and includes a control
treatment and replication in its design.
F. Identify the role and utility of control treatments, replication of treatments, and
sample size in any experiment.
2. What does it mean to be alive?
A. List the five characteristics all organisms on Earth share.
1) Energy - Organisms must acquire and use energy to stay alive and reproduce. E.g.
plants absorb sunlight; animals ingest food
2) Cells - Organisms are made of membrane-bound units called cells. Cells regulate the
passage of materials between exterior and interior spaces.
3) Information - Organisms process hereditary (genetic) information encoded in units
called genes. Organisms also respond to information from the environment + adjust
to maintain stable internal conditions.
4) Replication - Almost everything an organism does contributes to one goal: replacing itself
5) Evolution - Organisms are the product of evolution, and their populations continue to
evolve.
B. Explain why the first four are required for life.
1) Organisms require energy to stay alive and reproduce.
2) All organisms are made of cells.
3) The chemical reactions that sustain life take place inside the cells.
4) Cells contain genetic information that encodes for an organism to be alive.
5) Organisms also must respond to information from the environment and adjust
to maintain homeostasis.
,6) Cells must replicate during meiosis (sexual reproduction) to ensure that all
organisms contain the correct number of chromosomes.
C. Understand how the ability to perform work is related to being alive.
Anabolic and Catabolic reactions allow for all of the processes in our cells to occur.
Without work occurring within our bodies, we are unable to function (move, sleep,
eat, breathe)
D. Predict the direction of net flow of water across a cell membrane due to
osmosis given information about solute concentrations on either side of the
membrane. Explain what happens to rates of movement of water molecules in
both directions across the membrane at equilibrium.
Water flows into cells because there is higher concentration of salt inside a cell. So,
it moves from high to low concentration. When an equilibrium is met there is no
net movement of molecules, however, molecules are still moving randomly.
E. Understand that net flow of molecules due to osmosis is a result of the rates of
movement of particles in both directions, NOT as a result of an inherent
preference or force moving these molecules in one direction or the other.
Particles move randomly from bouncing off of each other, if there is a higher
concentration then particles will bounce off of each other more frequently and this
results in a desire to reach equilibrium
3.Be able to apply the First and Second Law of Thermodynamics
and explain their relevance to living processes
A. Define the First and Second Law of Thermodynamics.
1) First Law of Thermodynamics - Energy is conserved, it cannot be created or
destroyed, but only transferred and transformed
2) Second Law of Thermodynamics - entropy always increases in an isolated system
B. Use the First Law of Thermodynamics to explain how chemical reactions transfer
energy from one molecule to another.
1) Energy changes from one form to another (potential, kinetic).
2) Stored energy is called potential energy. An object gains or loses its
ability to store energy because of its position. Potential energy can be
converted to motion.
3) Kinetic energy is the energy of motion. Molecules have kinetic energy
because they are constantly in motion.
Thermal energy (heat)
Potential energy is stored in the bonds
When a reaction is endothermic it has to have energy put in
it When a reaction is exothermic is releases energy
C. Understand how molecules store chemical potential energy.
1) Associated with electrons in atoms
2) Most stable situation - negatively charged electron is very close to the
positively charged nucleus of an atom.
3) Further the electron is moved from the nucleus, the more chemical
potential energy it has.
4) More potential to convert this potential energy into kinetic energy and move
towards the nucleus (if given the chance)
5) Chemical energy is the energy involved in chemical reactions - elements
join together into compounds
6) Energy is stored inside the compounds as chemical potential energy
, 7) Energy can be released by further chemical reactions
8) When bonds are broken, potential energy is released
9) Two elements form a chemical bond, they share electrons
10) Element with higher electronegativity (ability to attract electrons)
grabs the shared electron more closely to its nucleus than the other
element
D. Determine whether a change of a system increases or decreases in
enthalpy (ΔH) and entropy (ΔS) over the course of the reaction.
1) In general, physical and chemical processes proceed in the direction
that results in increased entropy and lower potential energy
2) Spontaneous Reaction - products have lower potential energy than the
reactants (electrons in products are held more tightly than those in
the reactants)
3) Reaction wants to move in a direction that REDUCES the total internal
energy of the system
4) A reaction is favorable if entropy increases
5) Entropy (ΔS) - dispersal of energy and matter (disorder)
6) A reaction is favorable if enthalpy decreases (releases heat)
Enthalpy (ΔH) - amount of heat released or absorbed by a chemical reaction
E. Use the Second Law of Thermodynamics to predict whether a process is
exergonic or endergonic and thus will proceed spontaneously or not by
qualitatively applying the equation ΔG = ΔH – T*ΔS.
1) Gibbs Free Energy Equation
2) Change in Gibbs Free Energy = change in potential energy of the
system/change in the disorder of the system
3) When ΔG decreases, means energy is released and the reaction is spontaneous
4) Negative enthalpy (ΔH) reaction is spontaneous
5) Positive entropy (ΔS) reaction is spontaneous
6) Not all spontaneous reactions are exergonic
F. Define exergonic and endergonic chemical reactions.
1) Exergonic Reactions
Release energy (can be used to do work)
Tend to be spontaneous
Reactants have a higher Gibbs Free Energy than the
products ΔH (Enthalpy) is negative (heat given off)
ΔS (Entropy) is positive
2) Endergonic Reactions
Requires energy to be done on the system for the reaction to
proceed qΔH (Enthalpy) is positive (heat absorbed)
4. How do organisms control exergonic reaction rates?
A. Be able to draw a graph that illustrates activation energy in a graph of
the time course of a chemical reaction
