Understanding Equilibrium Constants and Gibbs Free Energy

The video tutorial explores a student's claim that a dehydration reaction at 298 Kelvin has an equilibrium constant less than 1. The instructor reviews the concepts of Gibbs free energy and equilibrium constants, explaining how to calculate Delta G using given thermodynamic data. The calculated Delta G is positive, indicating the reaction is non-spontaneous, supporting the student's claim. The tutorial further demonstrates how to relate Delta G to the equilibrium constant, confirming it is less than one, thus validating the student's assertion.

What does the student claim about the equilibrium constant at 298 Kelvin?

• It is less than 1.

• It is greater than 1.

• It is not defined.

• It is equal to 1.

Which concept should you review if equilibrium constants are unfamiliar?

• Khan Academy videos on thermodynamics

• Khan Academy videos on atomic structure

• Khan Academy videos on Gibbs free energy and equilibrium constants

• Khan Academy videos on chemical kinetics

What is the relationship between Delta G and equilibrium constants?

• Delta G is zero when equilibrium constant is less than 1.

• Delta G is always positive when equilibrium constant is greater than 1.

• Delta G can be used to determine if the equilibrium constant is greater or less than 1.

• Delta G is irrelevant to equilibrium constants.

What is the change in standard enthalpy given for the reaction?

• 45.5 kJ/mol

• 126 kJ/mol

• 298 kJ/mol

• 7,950 kJ/mol

Why is it important to convert all units to joules when calculating Delta G?

• To match the units of entropy

• To avoid using Kelvin

• To ensure consistency in calculations

• To make the calculation easier

What does a positive Delta G indicate about a reaction?

• The reaction is at equilibrium.

• The reaction is not spontaneous.

• The reaction is spontaneous.

• The reaction is exothermic.

How does Delta G relate to the energy available to do work?

• A negative Delta G means more energy is available to do work.

• A positive Delta G means more energy is available to do work.

• Delta G does not relate to energy available to do work.

• Delta G is only relevant at 0 Kelvin.

What happens to the equilibrium constant if Delta G is positive?

• It becomes undefined.

• It becomes less than 1.

• It becomes greater than 1.

• It remains unchanged.

What is the value of the equilibrium constant calculated in the video?

• 0.044

• 1.00

• 0.404

• 4.44

Why is the equilibrium constant less than one in this reaction?

• Because Delta G is negative

• Because Delta G is positive

• Because the reaction is at equilibrium

• Because the reaction is exothermic