The electricity on which the motor runs represents ATP.
ATP, adenosine triphosphate, is the energy currency of the cell. The energy released during the process of respiration is stored in the ATP molecule, and the ATP is stored within cells. Whenever the cell requires energy for any function, it simply hydrolyzes the ATP molecule, breaking a phosphate group off and releasing energy in the process.
Because the atom isn't a isotope. The electrons, (negative charge) , and the protons, (positive charge), balance each other out.
Basalt, rhyolite, andesite, and obsidian could all be answers.
