Delta G and Free Energy Concepts

Mr. McClain discusses free energy, focusing on Delta G and its role in chemical reactions. He explains how enthalpy and entropy contribute to the spontaneity of reactions, using examples to illustrate these concepts. The video also covers the differences between closed and open systems, emphasizing the importance of energy flow in living organisms. Key points include understanding Delta G, evaluating energy changes, and recognizing the significance of equilibrium.

What does Delta G represent in the context of free energy?

• The total energy of a system

• The change in free energy

• The temperature of a reaction

• The pressure of a system

Which of the following is true about a negative Delta G?

• It signifies a spontaneous reaction

• It is unrelated to the reaction's spontaneity

• It requires an input of energy

• It indicates a non-spontaneous reaction

In the free energy equation, what does enthalpy represent?

• The disorder of a system

• The total energy of a system

• The temperature in Celsius

• The pressure in atmospheres

What happens to Delta G when entropy increases in a system?

• Delta G becomes zero

• Delta G becomes more negative

• Delta G becomes more positive

• Delta G remains unchanged

Which of the following is an example of a process with negative Delta G?

• DNA replication

• Cellular respiration

• Photosynthesis

• Protein synthesis

What is required for a reaction with a positive Delta G to occur?

• An investment of energy

• A decrease in entropy

• No energy input

• An increase in enthalpy

How do catabolic reactions generally affect Delta G?

• They have no effect on Delta G

• They make Delta G positive

• They increase Delta G

• They decrease Delta G

What is a defining feature of open systems in living organisms?

• They reach equilibrium quickly

• They have a constant flow of energy

• They do not require energy input

• They are closed to external influences

What happens to a closed system when it reaches equilibrium?

• It continues to do work

• It stops doing work

• It requires more energy input

• It becomes more ordered

Why is disequilibrium important in living organisms?

• It allows for constant energy flow

• It leads to system shutdown

• It causes energy loss

• It results in no work being done