Gibbs Free Energy and Spontaneity

The video tutorial explains how to determine if a chemical reaction is spontaneous using Gibbs free energy. It introduces the concept of spontaneity, explains the components of Gibbs free energy (enthalpy and entropy), and provides a formula to calculate it. The tutorial includes an example problem to demonstrate how to determine the temperature at which a reaction becomes spontaneous. The key takeaway is that a reaction is spontaneous if the Gibbs free energy is negative, and the video provides tips for solving related problems.

What is the key factor in determining if a reaction is spontaneous?

• Entropy change

• Gibbs free energy

• Enthalpy change

• Temperature

Which of the following is NOT needed to calculate Gibbs free energy?

• Temperature

• Pressure

• Entropy change

• Enthalpy change

What does a negative Gibbs free energy indicate about a reaction?

• The reaction is spontaneous

• The reaction requires a catalyst

• The reaction is non-spontaneous

• The reaction is at equilibrium

In the given example, what is the value of Delta H?

• 411 kJ

• 158 J

• 411 J/K

• 158 kJ

Why is it necessary to convert Delta H to joules in the example problem?

• To match the units of Delta S

• To simplify the calculation

• To match the units of temperature

• To make the value smaller

What is the formula used to calculate Gibbs free energy?

• Delta G = Delta H + T Delta S

• Delta G = Delta H - T Delta S

• Delta G = Delta H * T Delta S

• Delta G = Delta H / T Delta S

What must be true for a reaction to be spontaneous in terms of Delta G?

• Delta G must be positive

• Delta G must be zero

• Delta G must be negative

• Delta G must be greater than Delta H

At what temperature will the reaction in the example become spontaneous?

• 158 K

• 411 K

• 384 K

• 273 K

What happens to the units of joules and Kelvin in the final step of solving for temperature?

• They remain unchanged

• They multiply

• They add up

• They cancel out

What is the key takeaway about driving reactions to be spontaneous?

• Increase the pressure

• Decrease the entropy

• Increase the temperature

• Decrease the enthalpy