Periodic Trend: Electron Affinity (Simplified)

electron affinity, which is abbreviated as E. A. Represents the energy released from the addition of an electron to a gashes atom or ion in killing jewels. So here let's say we have carbon gas. So here we're dealing with a gashes atom, we need to add an electron to it, adding an electron means that it will be reactive. The carbon absorbs that electronic gains a negative charge because electrons are negative. Now in order to connect them together, energy has to be released. This energy represents the electron affinity here. It has to be a product because it's being released now in chemistry. Of course they're exceptions that arise sometimes and this is one of them with electron affinity. The exception is we have electron affinities that are less than or equal to zero. And that happens when the element will not readily accept an electron. But why wouldn't an element want to accept an electron? Well, they may have a uniquely stable electron configuration or arrangement. I. E. The noble gases, we talked about noble gases being perfect if you're perfect in terms of the number of electrons you don't have a need of wanting to accept another electron. So the noble gases are a great example of elements that will not readily accept an electron. Now the general trend is electronic affinity increases as we move from left to right across the period and going up a group. Now, what does it mean that electron can easily accept an electron or not? Well, we're going to say here that if the lower your electron affinity then the electron will not easily be accepted. So the smaller electron affinity is the heart. It is for that elevator ion to accept an electron. And we're gonna stay here. That the greater your electronic affinity is then the more readily that ion or atom will accept an electron. Okay.

So electron affinity is not as clean cut as other periodic trends. There are exceptions that pop up all over the place even more. So with rose 56 and seven, so much so that you really don't need to pay attention to them. Now realize here that as we're heading towards the top right corner, electron affinity more or less will be increasing. Also remember that when it comes to the noble gases there electronically perfect. They don't want additional electrons. So their electron affinities are less than or equal to zero. We also see this trend pop up with nitrogen, zinc, manganese and in group to a beryllium, magnesium and calcium. Because there are electronic arrangements, they're also electronically stable. Not perfect, just stable and they don't readily accept an electron. So again, the general trends as we're heading towards the top right corner, electronic affinity increases, noble gases don't ever want to accept an electron. And then these other ones that I've circled also fit this idea of being electronically stable. So they also don't readily accept an electron. So keep this in mind when you're looking at electronic affinity

So here let's take a look at this example question. And I've left the periodic table here just to help us. It says which of the following halogen will release the most energy with the addition of an electron. Remember the general trend is as we're heading up towards a group electronic affinity more or less will be increasing. Now, if we take a look here, we have sulfur neon nitrogen asked the team and brahmi. All right. So first of all, a halogen is in group 78. So these are not even halogen, they're not in group seven. A. The answer is going to be either D. Or E. Realize here that I don't even show A. T. It's in one of the roles that we ignore because it's very unpredictable in terms of electronic affinity, which means that it wouldn't be a viable option. So it will be our answer here through the process of elimination. Now, of course, there are exceptions to electronic affinity. It's all over the place. We can see that the general trend should be as we go up a group, your electronic affinity increases, but you can see that actually chlorine has a slightly higher electron affinity than flooring. But here we don't have to worry about that because I wasn't asking about either one of those religions. It was between bromine and a statin instead. But just remember, the general trend is as we head up a group, Ultron affinity more or less will be increasing.