Question

Answer true or false to the following statements about energy diagrams and reactions. (a) A reaction coordinate diagram is used to visualize the change in the internal energy of chemical structures that occurs during chemical reactions. (b) Thermodynamics is the study of the energies of structures that are represented by wells on reaction coordinate diagrams. (c) Kinetics is the study of the rates of chemical reactions. (d) One part of a reaction mechanism would be the understanding of which bonds break and form during a reaction. (e) Thermal reactions occur via collisions between molecules, and the more energy in those collisions, the greater the rate of the reactions. (f) The enthalpy of a reaction is the sole determinant of whether it will occur. (g) An exergonic reaction will always occur during the life span of the standard human being.

Short answer

a) A reaction coordinate diagram is used to visualize the change in internal energy during chemical reactions. b) Thermodynamics is the study of the energies of structures represented by wells on reaction coordinate diagrams. c) The enthalpy of a reaction is the sole determinant of whether it will occur. d) An exergonic reaction will always occur during the life span of the standard human being. Answer: b, c, and d are false statements.

Step-by-step solution

Statement (a)

A reaction coordinate diagram is used to visualize the change in the internal energy of chemical structures that occurs during chemical reactions. True.

Statement (b)

Thermodynamics is the study of the energies of structures that are represented by wells on reaction coordinate diagrams. False. Thermodynamics is the study of the relationship between heat, work, and energy in a system.

Statement (c)

Kinetics is the study of the rates of chemical reactions. True.

Statement (d)

One part of a reaction mechanism would be the understanding of which bonds break and form during a reaction. True.

Statement (e)

Thermal reactions occur via collisions between molecules, and the more energy in those collisions, the greater the rate of the reactions. True.

Statement (f)

The enthalpy of a reaction is the sole determinant of whether it will occur. False. The enthalpy, entropy, and temperature together determine the spontaneity of a reaction by calculating the change in Gibbs free energy.

Statement (g)

An exergonic reaction will always occur during the life span of the standard human being. False. The spontaneity of an exergonic reaction is determined by the Gibbs free energy, but the kinetics may be slow, meaning the reaction might not occur or may occur over an extended period.