Why is ionisation energy endothermic

Improve this question. Nova Nova 1, 2 2 gold badges 25 25 silver badges 41 41 bronze badges. That also should hint at why it takes energy to remove an electron. It is very analogical to astronomical bodies bound by gravity of the central body. Note that ionization can be a part of more complex overall process that can be even highly exothermic. Add a comment.

Active Oldest Votes. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. Featured on Meta. Now live: A fully responsive profile. This process is exothermic. Atoms like the noble gases will not gain an electron because they are already in their most stable state with a full shell. Atoms like F will most likely gain an electron because when a free electron is added to the outer shell of fluorine, it will have obtained a full shell.

Generally, atoms increasing across a period will increase in EA also. When an electron is added to an atom, the energy change is exothermic because of the attraction of the electron to the nucleus. However, in the case of EA 2 where the electron is added to an anion, the repulsion between the anion and this newly added electron will overwhelm the attraction of the electron to the nucleus.

Therefore, this process will be endothermic, as opposed to EA 1. Electron Affinities Electron affinity, often abbreviated as EA, is the energy released when an electron is added to a valence shell of the atom. References Vedeneyer, Vladimir Ivanovich. London: Edward Arnold, Petrucci, Ralph. Maples said the vehicle was experiencing issues with its exhaust system at the time of the fire and the excess heat caused a package of hand warmers to melt into the carpet, intensifying the fire.

Most disposable hand warmers contain a mix of iron, water, activated carbon, vermiculite, cellulose, and salt. Once exposed to air, the iron oxidizes and releases heat in the process. After all the iron has reacted, the hand warmer is done and ready for the trash. It could explode and make a mess or damage the microwave.