Thermodynamics in Human Biology

Podcast

Play an AI-generated podcast conversation about this lesson

Download our mobile app to listen on the go

Get App

Questions and Answers

Which law of thermodynamics states that energy cannot be created or destroyed, only transferred or transformed?

First law of thermodynamics (correct)
Second law of thermodynamics
Third law of thermodynamics
Zeroth law of thermodynamics

Which law of thermodynamics states that the entropy of a closed system tends to increase over time?

Third law of thermodynamics
Second law of thermodynamics (correct)
First law of thermodynamics
Zeroth law of thermodynamics

Which law of thermodynamics states that as the temperature of a system approaches absolute zero, the entropy of the system approaches a minimum value?

Zeroth law of thermodynamics
Second law of thermodynamics
Third law of thermodynamics (correct)
First law of thermodynamics

Which concept in thermodynamics determines whether a process will occur spontaneously or not?

Gibb's free energy (A) Signup and view all the answers

Which equation represents the relationship between enthalpy, entropy, and temperature?

(\Delta G = \Delta H - T\Delta S) (C) Signup and view all the answers

Which equation represents the relationship between enthalpy, entropy, and temperature for a spontaneous process?

(\Delta G < 0) (A) Signup and view all the answers

Which equation represents the relationship between enthalpy, entropy, and temperature for a non-spontaneous process?

(\Delta G > 0) (B) Signup and view all the answers

Which equation represents the relationship between enthalpy, entropy, and temperature at equilibrium?

(\Delta G = 0) (B) Signup and view all the answers

Which equation represents the relationship between enthalpy, entropy, and temperature for a reversible process?

(\Delta G = \Delta S + T\Delta H) (B) Signup and view all the answers

Which concept in thermodynamics describes the maximum amount of useful work that can be obtained from a system at constant temperature and pressure?

Gibb's free energy (A) Signup and view all the answers

Which one of the following statements is true about the first law of thermodynamics?

The total amount of energy in a closed system remains constant in any chemical change. (D) Signup and view all the answers

Which one of the following statements is true about exothermic reactions?

They have a negative ΔH. (A) Signup and view all the answers

Which one of the following statements is true about endothermic reactions?

They have a positive ΔH. (C) Signup and view all the answers

Which one of the following statements is true about the second law of thermodynamics?

Energy disperses or spreads out unless hindered from doing so. (C) Signup and view all the answers

Which one of the following statements is true about Gibbs Free Energy?

It measures the energy difference between the products and reactants. (C) Signup and view all the answers

Which one of the following reactions would be spontaneous?

ΔH = -5 kJ/mol, ΔS = -10 J/mol·K (B) Signup and view all the answers

Which one of the following reactions would be non-spontaneous?

ΔH = 5 kJ/mol, ΔS = 10 J/mol·K (C) Signup and view all the answers

Which one of the following reactions would be at equilibrium?

ΔH = -10 kJ/mol, ΔS = -5 J/mol·K (A) Signup and view all the answers

Which one of the following reactions is exergonic?

ΔG = -5 kJ/mol (D) Signup and view all the answers

Which one of the following reactions is endergonic?

ΔG = 5 kJ/mol (A) Signup and view all the answers

Which of the following is true about a reaction with a negative ΔHrxn and a positive ΔSsystem?

It will sometimes have a positive ΔG (A) Signup and view all the answers

When products and reactants are not both at 1 M, how does it impact the Gibbs free energy?

It depends on the specific reaction (C) Signup and view all the answers

For a hypothetical reaction with a ΔGoʼ of 5.0 kJ/mol, what happens to the Gibbs free energy as the reactants are increased compared to the products?

The Gibbs free energy always increases (C) Signup and view all the answers

What is the rationale for why the body phosphorylates ATP as a source of energy currency?

ATP has a negative ΔG when broken (D) Signup and view all the answers

Do enzymes themselves change the ΔG of a reaction?

No, enzymes cannot change the ΔG of a reaction (A) Signup and view all the answers

What is the equation to calculate the Gibbs free energy under non-standard conditions?

ΔG = ΔGoʼ + RT lnQ (B) Signup and view all the answers

What is the equation to calculate the Gibbs free energy change of a reaction?

ΔG = ΔH - TΔS (B) Signup and view all the answers

What does the reaction quotient (Q) represent in the equation for Gibbs free energy under non-standard conditions?

The equilibrium constant (C) Signup and view all the answers

What is the relationship between ΔG and ΔGoʼ for a reaction under non-standard conditions?

It depends on the specific reaction (B) Signup and view all the answers

What is the activation energy of a reaction?

The energy required to initiate the reaction (C) Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Laws of Thermodynamics

The first law of thermodynamics states that energy cannot be created or destroyed, only transferred or transformed.
The second law of thermodynamics states that the entropy of a closed system tends to increase over time.
The third law of thermodynamics states that as the temperature of a system approaches absolute zero, the entropy of the system approaches a minimum value.

Thermodynamic Concepts

Gibbs Free Energy (ΔG) determines whether a process will occur spontaneously or not.
The equation ΔG = ΔH - TΔS represents the relationship between enthalpy, entropy, and temperature.
For a spontaneous process, ΔG < 0.
For a non-spontaneous process, ΔG > 0.
At equilibrium, ΔG = 0.
For a reversible process, ΔG = 0.

Thermodynamic Relationships

The maximum amount of useful work that can be obtained from a system at constant temperature and pressure is described by the concept of available work.
The equation ΔG = ΔG° + RT ln(Q) represents the relationship between Gibbs free energy and reaction quotient under non-standard conditions.

Reaction Types

Exothermic reactions release heat, ΔH < 0.
Endothermic reactions absorb heat, ΔH > 0.
A reaction is spontaneous if ΔG < 0.
A reaction is non-spontaneous if ΔG > 0.
A reaction is at equilibrium if ΔG = 0.
An exergonic reaction has a negative ΔG and is spontaneous.
An endergonic reaction has a positive ΔG and is non-spontaneous.

Reaction Conditions

When products and reactants are not both at 1 M, the Gibbs free energy is affected.
As reactants are increased compared to products, the Gibbs free energy decreases.
The equation ΔG = ΔG° + RT ln(Q) is used to calculate the Gibbs free energy under non-standard conditions.

Biological Energy

The body phosphorylates ATP as a source of energy currency.
Enzymes do not change the ΔG of a reaction, but they lower the activation energy.

Gibbs Free Energy Equations

The equation ΔG = ΔH - TΔS represents the relationship between enthalpy, entropy, and temperature.
The equation ΔG = ΔG° + RT ln(Q) represents the relationship between Gibbs free energy and reaction quotient under non-standard conditions.
The equation ΔG° = -RT ln(K) represents the relationship between Gibbs free energy and equilibrium constant.

Reaction Quotient and Gibbs Free Energy

The reaction quotient (Q) represents the ratio of product concentrations to reactant concentrations.
The relationship between ΔG and ΔG° for a reaction under non-standard conditions is ΔG = ΔG° + RT ln(Q).
The activation energy of a reaction is the minimum energy required for a reaction to occur.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.