Final answer:
The energy change that occurs when an electron is added to a neutral gaseous O atom, forming an O- ion, is called the electron affinity (EA). For Oxygen (O), the electron affinity is positive, meaning that energy needs to be added to the system to produce an O- ion.
Step-by-step explanation:
The energy change that occurs when an electron is added to a neutral gaseous O atom, forming an O- ion, is called the electron affinity (EA). This process can be either endothermic or exothermic, depending on the element. For Oxygen (O), the electron affinity is positive, meaning that energy needs to be added to the system to produce an O- ion. Therefore, the correct answer is d. +710 kJ.