Electronegativity Trends
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Electronegativity Trends
How would we determine which element has a higher/ lower electronegativity if one element is one 'block' further to the right while the other is one 'block' up? For example, if we were looking at N and S, which would have the higher electronegativity and why?
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Re: Electronegativity Trends
Hi! The trend for electronegativity is the same as ionization energy. So, electronegativity increases from left to right across a period and decreases down a group. However, this trend does not apply to the noble gases because they do not want another electron. In the case of N and S, nitrogen would be more electronegative than sulfur because elements in the upper right hand corner of the periodic table are most electronegative, like N,O, and F. We can also confirm this by looking up the electronegativity of Nitrogen, 3, and of sulfur, 2.6, and seeing which one is greater.
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Re: Electronegativity Trends
So, it is really hard to differentiate between the two values of EN in the example you described but there are some ways that you can tell. Nitrogen which you mentioned is able to hydrogen bond but Sulfur is not. Since we have this knowledge we know that N is more electronegative since one of the requirements for hydrogen bonding is that a hydrogen is attached to the most electronegative atoms.
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Re: Electronegativity Trends
Kind of as a follow-up question, how would you determine which element in a molecule would create a bigger difference in electronegativity? Like when trying to compare two molecules' iconic character?
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Re: Electronegativity Trends
isha dis1k wrote:Kind of as a follow-up question, how would you determine which element in a molecule would create a bigger difference in electronegativity? Like when trying to compare two molecules' iconic character?
I think you look for the molecule where the elements are furthest apart on the periodic table. If they're further apart, then their electronegativity difference should be greater and it should have more ionic character.
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Re: Electronegativity Trends
isha dis1k wrote:Kind of as a follow-up question, how would you determine which element in a molecule would create a bigger difference in electronegativity? Like when trying to compare two molecules' iconic character?
In order to determine the exact difference in electronegativity you would need to be given the values. However, if on a test or quiz no values are given you can assume that the molecules that are further away from each other on the periodic table have the bigger difference in electronegativity.
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Re: Electronegativity Trends
Does anyone know how noble gases were experimentally proven to not have any electron affinity. Again, experimentally, not conceptually.
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Re: Electronegativity Trends
So according to these trends, what would the most electronegative element be? Fluorine?
Re: Electronegativity Trends
When drawing the lewis structure of a molecule would we take into consideration of the atoms individual electronegativity? If so, how would that play into drawing the structure?
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Re: Electronegativity Trends
Emily_Stenzler_2H wrote:How would we determine which element has a higher/ lower electronegativity if one element is one 'block' further to the right while the other is one 'block' up? For example, if we were looking at N and S, which would have the higher electronegativity and why?
I think N should have similar electronegativity with S, due to something called diagonal rule. But this might not be included in our syllabus.
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Re: Electronegativity Trends
isha dis3d wrote:Kind of as a follow-up question, how would you determine which element in a molecule would create a bigger difference in electronegativity? Like when trying to compare two molecules' iconic character?
I think you can look at their position in the periodic table, like more closer to the top right corner, then the higher electronegativity.
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Re: Electronegativity Trends
Of course the general trend is that electronegativity increases as you move up and towards the right of the periodic table, excluding noble gases. With N and S, N is more electronegative (electronegativity of 3.0 vs Sulfur 2.6). I tend to just look up the electronegativities when it gets too difficult to distinguish based on periodic table trends alone.
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Re: Electronegativity Trends
So electronegativity trends general represented as the following: decreases down a row and increases across a period. It decreases down a row because the subsequent outer shells get farther and farther away from each other as the atomic number increases. Electronegativity increases across a period because the electrons stay in the same shell but the positive charge of the nucleus increases making it harder for an electron to be removed.
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