Which is true for a substance that releases energy? a. the energy release decreases the molecular motion and the kinetic energy of the substance. b. the energy release decreases the molecular motion but increases the kinetic energy of the substance. c. the energy release increases the molecular motion and the kinetic energy of the substance. d. the energy release increases the molecular motion but decreases the kinetic energy of the substance. e. the energy release is used only to change the state of the substance.

The correct answer is option A, that is, the energy release decreases the molecular motion and the kinetic energy of the substance.

When a substance discharges energy, it signifies that the energy of the molecules is now being transferred into the substance with whom it comes in contact with or into the atmosphere. Thus, at the time of the discharge of energy, the motion of molecules diminishes and as a consequence, the kinetic energy of the molecules will reduce.  

Therefore, it can be concluded that for a substance the energy discharged diminishes the molecular motion and the kinetic energy of the substance.  

the answer for sodium is 0.186

the answer for rubidium is 0.251