Questions tagged [electron-affinity]
The amount of energy released when an electron is added to a species in the gaseous phase to form a negative ion. Not to be confused with [ionization-energy].
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Is the magnitude of ionisation enthalpy and ionisation energy is same?
In my textbook it is written that ionisation energy and ionisation enthalpy are two different quantities. ionisation energy is the amount of energy provided to extract an electron from the outermost ...
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Trends of electron affinity
The trend in electron affinity is to increase negatively across a group.
Does this mean noble gases' electronegativity is more negative than halogens?
Noble gases should have a positive electron ...
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Why is the first electron affinity exothermic and successive ones endothermic?
I am having trouble wrapping my head around electron affinities. And the textbook explanations aren't very helpful.
So, the textbook says that the 1st electron affinity is generally exothermic. The ...
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Are 1st Electron Affinities positive or negative?
According to this ChemistryLibretexts website and this StackExchange answer, 1st electron affinites are negative and 2nd electron affinities are positive.
However, according to this Study.com ...
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How can chlorine be 'only' the third-most electronegative element yet have the highest electron affinity?
From Wikipedia:
It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the Pauling scale,...
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Electron Affinity of Carbon and Silicon
Which has the greater affinity for an electron, Si or C and why? When thinking about the exception with F and Cl I would expect Si to have a greater electron affinity than C, but when I look at ...
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Electron affinity of isotopes anomaly
According to the Wikipedia article the electron affinity of $\ce{^{2}H}$ is higher than the electron affinity of $\ce{^{1}H}$ however the electron affinity of $\ce{^{18}O}$ is lower than $\ce{^{16}O}$....
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Why is there not a strict correspondence between electronegativity and ionic character?
Why is the Electronegativity difference for atoms in bonding uncertain while determining what the compound will be?
According to the IB(International Baccalaureate) they say that the ...
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The first electron affinity of an atom
I've read that the first electron affinity is always negative, meaning that energy is always released upon the addition of this first electron. However, I don't think this will apply to noble gases. ...
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Why are the electron affinity values of alkali metals still negative, despite the process being endothermic?
I understand that electron affinity is generally exothermic(groups 16 and 17). But, alkali metals are reluctant to gain an electron because losing electrons is beneficial for them. So, the electron ...
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Most stable monoatomic ion of nitrogen [closed]
I often see that the most stable monoatomic ion of nitrogen is N$^{3-}$ (for example on Khan Academy), and I remember being taught something similar, along the lines of atoms wanting complete octets.
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Are diffuse functions necessary for modeling unbound conjugated anions?
According to this paper, and contrary to popular belief, diffuse functions are far from being necessary for the calculation of the electron affinities of the polycyclic aromatic hydrocarbon(PAH)s, due ...
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Are there any monocations with negative electron affinities known?
It is known that most dianions are unbound per se, i.e. that the corresponding monoanions have negative electron affinities, and the "dianions" we see in e.g. metal oxides can exist as such ...
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Electron affinities of the alkali and alkali earth metals
According to my book, the former has a higher EA than the latter group of elements because alkali metals will attain $ns^2$ configuration whereas an alkaline earth metal in the same period will attain ...
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Confusion regarding 1st and 2nd electron gain enthalpy
$\ce{O}$ has the 1st electron gain enthalpy $\pu{-141 kJ mol-1}$. $-ve$ value implies that energy is released when electron is added to an isolated atom. This also means that if $\pu{141 kJ}$ energy ...
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Why does titanium have lower affinity than scandium?
Electron affinity of atoms in the same row usually increases with the atomic number until the shell or half-shell gets full, and then it drops down. Some transition metals are exceptions from the rule,...
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Why do alkali metals have an exothermic electron affinity?
Alkali metals should have positive electron gain enthalpies as they are electropositive elements and also their atomic sizes are larger in their periods so they should be reluctant to take electrons ...
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Why does tennessine have a larger (predicted) electron affinity than nihonium?
According to Wikipedia, tennessine has an electron affinity (EA) of $\pu{+166 kJ mol-1}$ and nihonium $\pu{+67 kJ mol-1}$.
Normally this would make sense since tennessine is in group 17 and nihonium ...
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Why is Electron Gain Enthalpy of only Be and Mg positive, in group 2?
While going through my book, I came across the following observation:
$\Delta H_{eg1}$ is positive for Be and Mg
Where $\Delta H_{eg1}$ is the first electron gain enthalpy.
It seemed quite ...
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First ionization energy and electron gain enthalpy of dihydrogen / stability comparison of dihydrogen ions [duplicate]
Subset of: How can antibonding orbitals be more antibonding than bonding orbitals are bonding?
Stability of $\ce{H2^{-}}<\ce{H2^{+}}<\ce{H2}$
Stability of $\ce{N2^{-}}<\ce{N2^{+}}<\ce{N2}...
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Electron affinity of nitrogen and exchange energy
When studying the effects of electron filling in chemistry, I was studying why energy is needed to add an electron to a nitrogen atom i.e. electron affinity.
Nitrogen already has an electron ...
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What exactly is lattice energy?
I was going through my chemistry textbook (Chemistry, 10th Ed. by Raymond Chang) when I encountered this explanation of lattice energy.
9.3 Lattice Energy of Ionic Compounds
We can predict which ...
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Why do selenium , tellurium and polonium have more negative electron gain enthalpy than oxygen?
In my book(NCERT Chemistry Part I, Textbook for Class XI[1]) a list of values of electron gain enthalpies of various elements is given. According to that list, oxygen has less negative electron gain ...
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Why energy is released when an electron is added to a neutral atom? [duplicate]
Question :
Why energy is released when an electron is added to a neutral atom?
I read somewhere
“When electrons are added to an atom, the increased negative charge puts stress on the electrons ...
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Why is electron gain generally exothermic?
I understand that we need to supply energy to counter the nuclear attraction when we remove electrons, and that is the reason why ionization energy is endothermic. However, why does an atom release ...
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While electrolyzing concentrated aqueous sodium chloride, why is it that chlorine is discharged but not sodium?
Hydrogen and hydroxide both exceed sodium and chlorine in terms of reduction and oxidation potential respectively.
While electrolyzing a concentrated solution of aqueous NaCl, it is known that ...
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Why does boron have a lower affinity than oxygen? [closed]
Electron affinity of oxygen is 141 kJ/mol and electron affinity of boron is 27 kJ/mol. I suspect it is because boron nucleus is much better shielded than oxygen nucleus (in the p-shell), but I am not ...
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Find the Ionisation Potential and Electron affinity of X
$N_0/2$ atoms of $X_{(g)}$ are converted into $\ce{X^+_{(g)}}$ by energy $E_1$. $N_0/2$ atoms of $X_{(g)}$ are converted into $\ce{X^-_{(g)}}$ by energy $E_2$.
Hence ionisation potential and electron ...
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Why do neutral metal atoms have affinity towards electrons? [duplicate]
Since first electron affinity is almost always negative, neutral atoms of most elements (including metals) must have an affinity towards electron. But shouldn't metals want to lose electron(s) rather ...
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Regarding comparison of ionization energies [closed]
Why is the ionization energy of $\ce{Mg^2+}$ greater than the ionization energy of $\ce{Ne}$ (neon)?
My teacher said the answer was $\ce{Mg^2+}$ but I have no idea why as my general knowledge tells ...
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More Anti-bonding or less bonding electrons?
Is a molecule more stable with less bonding electrons or more anti-bonding electrons? This question arose when I was asked the stability comparison between $\ce{N2^+}$ and $\ce{N2^-}$.
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When is the process exothermic and when is it endothermic? [closed]
When electrons are being added/removed from atoms or ions how can I tell if the process is exothermic or endothermic? For example in the question below, how could I tell for sure which of the ...
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Electron affinities of the chalcogens and halogens
Here are the electron affinities of the 16th and 17th groups.
The general trend for electron affinity down the group is that it decreases because of the increase in atomic radius.The exception of $\...
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If Oxygen has a lower electron affinity than Sulfur, then why doesn't sulfur has a lower electron affinity than selenium?
I've read that oxygen has a lower electron affinity (as shown the picture below), because it has a smaller atomic radius than sulfur and thus the electrons experience significant electron-electron ...
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Why does the electron affinity increase become more exothermic down group 2 and group 5?
It is generally true that the electron affinity becomes less exothermic down a group, because of the increase in atomic radius.
There is a well-known exception that the electron affinity of Cl is ...
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Electron Gain Enthalpy [duplicate]
When an electron ($e^-$) is added to $\ce{Cl}$ ,i.e.,
$$\ce{Cl + e^- -> Cl^- + ∆_{gh}H}$$
We can see that energy is released. My question is where is this energy coming from? What happens within ...
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Why does cesium have a positive electron affinity?
When an electron is added to cesium, why is energy released?
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Amphoterism and the Metal and Non-Metal Oxides/Hydroxides. Why does amphoterism occur in these? [closed]
I am having trouble understanding why Beryllium Oxide and Aluminum Oxide are amphoteric. Also, while they are not oxides, Aluminum and Beryllium Chloride as well.
Most of the things I have been ...
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Why do Hydrogen Halides(with the exception of HF) form mostly strong acids? [duplicate]
Why do Hydrogen Halides(with the exception of HF) form mostly strong acids?
My guess is that the negatively charged Halide part of the molecule is attracted by the partially positive part of the water ...
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How to get the second electron affinity of tellurium?
I need the value of the second electron affinity of Te, i.e. the energy change associated with the attachment of an electron to a $\ce{Te-}$ anion
$$\ce{Te- + e- -> Te^{2-}}$$
In the books (e.g. J. ...
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If fluorine has a lower electron affinity than chlorine, why does it have a higher ionization energy?
I have read that fluorine has a lower electron affinity than chlorine despite its lower atomic radius because its electron cloud is extremely dense. If this is the case, shouldn't the ionization ...
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Relation between electron gain enthalpy and electron affinity
The correct relation between electron gain enthalpy $(Δ_\mathrm{eg}H)$ and electron affinity $A_\mathrm{e}$ at any temperature '$T$' is
A) $Δ_\mathrm{eg}H = -A_\mathrm{e} - \frac{5}{2}RT$
B) $Δ_\...
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2nd Electron Affinity of halogens
I have seen questions regarding EA but they were all about the 1st EA so this question is not duplicate.
I came across a statement which goes like "2nd EA of halogens is almost zero". How is this ...
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Why it the electron affinity of beryllium is greater than nitrogen? [closed]
As we know that fully filled electronic configuration is more stable than half filled electronic configuration, so in my opinion beryllium's electron affinity should be less than nitrogen's.
Is my ...
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Why is fluorine more reactive than chlorine?
Why is fluorine more reactive than chlorine despite chlorine having a higher electron affinity?
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How to find out which organic molecules would be good electron acceptors/donors on a GaAs semiconductor surface [closed]
I'm a physicist in way over my head.
I have a list of organic molecules to investigate, all common aldehydes and amines. My supervisor wishes to know which of these molecules would be good electron ...
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Why do atoms have electron Affinity? [duplicate]
Atoms are stable so how can they pull electrons i.e how do they have any electron affinity at all?
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Why does oxygen have less negative electron gain enthalpy than sulphur? [duplicate]
Oxygen has less negative electron gain enthalpy than sulphur.
This statement is given in my book with a short reason:
due to compact size of oxygen
I'm unable to understand why. I would ...
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Why does oxygen not like to be a double anion?
The electron affinity of a neutral oxygen atom is −142 kJ (it releases this energy). The electron affinity for the now double anion $\ce{O^2-}$ is 710 kJ (work must be done on the atom).
My question ...
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Why don't gases of elements with negative electron affinities exist as ions in nature?
Fluorine has an electron affinity of about -300 kJ/mol. Lithium has an electron affinity of about 60 kJ/mol.
As I understand it when $\ce{Li^-}$ loses an electron about 60 kJ/mol is released but when ...
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