Understanding Electron Affinity and Ionization Potential in Chemistry

  • Thread starter Thread starter devanlevin
  • Start date Start date
  • Tags Tags
    Chemistry
AI Thread Summary
Electron affinity (EA) is defined as the energy released when an electron is added to a gas-phase atom, generally increasing from left to right across the periodic table and decreasing down a group. The ranking of elements by EA for Li, K, N, and C is debated, with one participant asserting C > Li > K > N, while another argues N > C > Li > K based on atomic radius. The discussion highlights exceptions to the general trends, particularly concerning nitrogen's relatively low EA despite its position on the periodic table. Participants reference a resource for EA values in kJ/mol to clarify their points. Overall, the conversation emphasizes the complexities of EA and ionization potential in chemistry.
devanlevin
In chemistry, what are the laws for finding electron affinity?
i need to rate these elements, from highest electron affinity to lowest, using only a periodic table, and the laws of electron affinity
Li K N C
the answer is
C> Li> K> N

i then need to do the same for Ionization potential
 
Physics news on Phys.org
Electron affinity (EA) is essentially the energy released when an electron is added to a gas-phase atom. EA increases as you move from left to right across the periodic table. And it decreases as you move down the table. The same increase/decrease relationship can be applied to ionization energy (though I'm not 100% sure if ionization energy <=> ionization potential)
 
from what i understand there are exception to that rule, something to do with symetry of the electron configuration,
like in this excercise
N is the furthest to the right and in the highest row of the 4 but has the smallest ea,
 
devanlevin said:
from what i understand there are exception to that rule, something to do with symetry of the electron configuration,
like in this excercise
N is the furthest to the right and in the highest row of the 4 but has the smallest ea,

hi

we have just finished the Electron-negativity, Ionization Potential and Electron Affinity Chapter

are you sure that N has the smallest EA?

if i had given a question like the one above, my answer would be this:

N > C > Li > K

my answer is according to the Atomic Radius of each Atom

as you can see N has the smallest Atomic Radius and K has the biggest.





( I'm sorry if my English is not understood :blushing:)
 
http://www.rzuser.uni-heidelberg.de/~ltemgoua/chemistry/Electron_affinity.html

check it out, the numbers are the EA in Kj/mol, not exactly the way you guys say
 
Last edited by a moderator:
devanlevin said:
http://www.rzuser.uni-heidelberg.de/~ltemgoua/chemistry/Electron_affinity.html

check it out, the numbers are the EA in Kj/mol, not exactly the way you guys say

hi again!

I'm sorry, I think if this question was asked to students that specialized in Chemistry,
They would have known about the exception.

but for me I'm an 11th grade student.

in answering either EA comparisons questions or any of the other related topics i follow the rule given in the link.

"Eea increases across a period (row) (since the radius slightly decreases, because of the increased attraction from the nucleus, and the number of electrons in the top shell increases, helping the atom reach maximum stability) in the periodic table and decrease going down a group (family) (because of a large increase in radius and number of electrons that decrease the stability of the atom, repulsing each other)".

but after seeing the link I think your answer is correcttake care!
 
Last edited by a moderator:
Thread 'Confusion regarding a chemical kinetics problem'
TL;DR Summary: cannot find out error in solution proposed. [![question with rate laws][1]][1] Now the rate law for the reaction (i.e reaction rate) can be written as: $$ R= k[N_2O_5] $$ my main question is, WHAT is this reaction equal to? what I mean here is, whether $$k[N_2O_5]= -d[N_2O_5]/dt$$ or is it $$k[N_2O_5]= -1/2 \frac{d}{dt} [N_2O_5] $$ ? The latter seems to be more apt, as the reaction rate must be -1/2 (disappearance rate of N2O5), which adheres to the stoichiometry of the...
Back
Top