Electron Affinity

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Emily_Bennett_3C
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Joined: Wed Sep 21, 2016 3:00 pm

Electron Affinity

Postby Emily_Bennett_3C » Mon Oct 24, 2016 8:50 pm

What do they mean when they ask for the higher or lower electron affinity?

Chem_Mod
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Re: Electron Affinity

Postby Chem_Mod » Mon Oct 24, 2016 9:40 pm

Electron affinity is the likelihood of an atom to gain an electron. The trend generally goes as follows: electron affinity increases from left to right across a period and decreases down a group on the periodic table.

Christopher Reed 1H
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Re: Electron Affinity

Postby Christopher Reed 1H » Mon Oct 24, 2016 9:43 pm

Hi!

Electron affinity is how much an atom wants to gain an electron. An atom will want to gain an electron if is super close to obtaining a half full orbital, a full orbital, or an octet in terms of valence electrons.

In terms of periodicity, electron affinity increase from left to right and bottom to top. The elements with the highest electron affinity (in decreasing order) are Cl > F > Br > I. Notice how Cl and F do not follow the trend I previously mentioned as chlorine is lower the fluorine yet it has a greater electron affinity. Also notice how these are all one electron away from being a noble gas! These guys really want that extra electron in order to obtain the stability of a noble gas.

Edit: I forgot to mention another exception to the trend which is carbon has a higher electron affinity than nitrogen. If you draw the aufbau diagram for both these elements you can see that carbon only needs on more electron to obtain a half full 2p orbital. It is important to remember that atoms want half or full orbitals so a useful strategy in comparing electron affinity might be to draw the aufbau diagram in cases where you are not sure.

Alexandra_Cooper_4H
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Re: Electron Affinity

Postby Alexandra_Cooper_4H » Wed Oct 26, 2016 5:51 pm

Will we have to know the formula for electron affinity for the quiz tomorrow? Does anyone know?

604744616
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Joined: Sun Jun 25, 2017 3:00 am

Re: Electron Affinity

Postby 604744616 » Mon Jul 10, 2017 8:05 am

How should we go about with memorizing or just remembering the trends in the periodic table? Any suggestions? And how can we also go about of remembering the exceptions in the periodic table?

Joe Rich 1D
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Re: Electron Affinity

Postby Joe Rich 1D » Sat Jul 15, 2017 11:34 am

Hey!

I like to remember trends by thinking of how a trend changes as you move up and to the right of the periodic table. Atomic radius and ionic radius are the biggest in the bottom left (at Cesium), and generally decrease as you move up and to the right. Ionization Energy, Electron Affinity, and Electronegativity are the biggest in the top right (Fluorine), and they decrease as you move down and left. Hope this trick helps!

Ben Rolnik 1D
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Joined: Fri Jun 23, 2017 11:39 am

Re: Electron Affinity

Postby Ben Rolnik 1D » Sat Jul 15, 2017 2:56 pm

just to add onto this -- since there were no homework problems which required performing electronegativity calculations, then you can be pretty sure questions like these won't show up on the tests.

In general, I would suggest focusing on the specific questions that arise from the homework problems. Otherwise you may be going above and beyond the course material (which we also never covered in lecture).

Hope that helps!

Tara 1F
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Joined: Fri Jun 23, 2017 11:39 am

Re: Electron Affinity

Postby Tara 1F » Sun Jul 16, 2017 5:07 pm

Do you think in our exam next thursday the 24th that we will be asked questions that relate to the trends in the periodic table ? If so does anyone know a good way to remember them!

derek1d
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Joined: Wed Jun 28, 2017 3:00 am

Re: Electron Affinity

Postby derek1d » Sun Jul 16, 2017 9:03 pm

I don't believe so. Apparently, the test next Tuesday will cover all new material since Exam 1 but not including topics from Exam 1 like the periodic trends.

Nancy 1B
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Joined: Wed Sep 21, 2016 2:58 pm

Re: Electron Affinity

Postby Nancy 1B » Sun Jul 16, 2017 10:29 pm

I don't think there is a test on Tuesday... unless I'm mistaken?

smuhammad1Section1E
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Joined: Thu Feb 02, 2017 3:00 am

Re: Electron Affinity

Postby smuhammad1Section1E » Sun Jul 16, 2017 11:31 pm

So from my understanding, there is a way to calculate the electron affinity...if that is the case, how would I go about doing such calculations.

Tara 1F
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Re: Electron Affinity

Postby Tara 1F » Mon Jul 17, 2017 8:49 pm

The test is next thursday the 24th :)

Tara 1F
Posts: 21
Joined: Fri Jun 23, 2017 11:39 am

Re: Electron Affinity

Postby Tara 1F » Tue Jul 18, 2017 12:01 am

Oops I mean thursday the 27th.


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