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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Why does chlorine have a higher electron affinity than fluorine?

Since fluorine has its valence electrons in the n=2 energy level, and since chlorine has its valence electrons in the n=3 energy level, one would initially expect that an electron rushing towards ...
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Are there any major exceptions when comparing electron affinity?

I was tasked with figuring out whether carbon or nitrogen has a more negative electron affinity value. I initially picked nitrogen, just because nitrogen has a higher $Z_\mathrm{eff}$, creating a ...
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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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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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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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is it possible to break the bonds of diatomic elements such as fluorine or iodine and create positive and negative ions by electron bombardment?

If I had a container in vacuum filled with $\ce{I2}$ gas and then I bombarded it with high speed electrons using an electron gun, would be able to get both $\ce{I+}$ and $\ce{I-}$ ions or would I ...
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Which element has a greater second electron affinity, sulfur or oxygen?

I found a question asking the above which states that sulfur has a lesser second electron affinity than oxygen. But since the inter-electronic repulsion in sulfur is lesser, shouldn't it be willing to ...
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What determines the electronegativity of an element?

Is it possible to work out without post-Bohrian mathematics?
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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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Why do alkali metals have an exothermic electron affinity?

Alkali metals should have positive electron gain enthalpy as they are electropositive elements and also there atomic size is big in their periods so they should be reluctant to take electrons but they ...
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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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On a periodic table it shows that Zn and Cd and Hg all have 0 electron affinity. Why is that?

Question On a periodic table it shows that Zn and Cd and Hg all have 0 electron affinity. Why is that? What I've noticed I've noticed that these three elements are the end of the D orbital and they ...
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Why does K have a greater electron affinity than Ca?

Why will $\ce{K}$ have a greater electron affinity than $\ce{Ca}$? I know that $\ce{Ca}$ has a greater first ionization energy, and I also know that $\ce{K}$ has a greater second ionization energy, ...
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Electronegativity

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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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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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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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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Is there a relation between the ionization energy and the electron affinity?

I am aware of the definition and equation of IE and EA. I was wondering if there is a direct relation between this two quantities with the energy of the neutral specie.
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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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Ca energy release when gaining an electron

Why does $\ce{Ca}$ have a negative electron affinity, i.e. energy is released when it gets an electron (ca. $\pu{-2 kJ/mol}$), when $\ce{Be}$ and $\ce{Mg}$ have positive values? I know that the ...
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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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Electronegativity and anion stability

If two similar sized atoms have different electronegativity values, the atom with higher electronegativity holds the electrons more tightly, and thus is more stable. Example: hydroxide vs azanide (NH2-...
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For group 7 elements, are anions a lower energy state than being neutral atoms?

Given that electron affinity is positive, why don't these atoms attract free electrons and "prefer" to exist as anions? Never made sense to me — I could be missing something obvious.
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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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Which atom goes in the middle of a lewis dot structure?

I've read online in multiple sites that the least electronegative atom goes in the middle with the exception of H, which always goes on the outside. However, in the molecule NaCN, C is in the middle. ...
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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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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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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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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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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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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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Using electron affinity to calculate lattice energy

I am trying to calculate the lattice energy of $\ce{CaBr2}$, I am uncertain of how to incorporate the electron affinity value provided for $\ce{Br2}$ into my calculation. Since electron affinity is ...
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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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Electron Affinity trends

Imagine an arrangement of atomic orbitals in an alternate universe, in which the s subshell contains 2 orbitals instead of 1, and the p subshell contains 4 orbitals rather than 3. In which groups ...
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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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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 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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1answer
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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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Is there any mathematical formula for electron affinity and ionization potential?

I already know about the mathematical formula for electronegativity, but it requires the ionization potential and electron affinity. How can I can easily calculate the ionization potential and ...
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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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Trend of second Electron Affinity for N,O,F,P,S,Cl

I am aware of the definition of electron affinity and electron gain enthalpy (EGE). N has positive EGE1, and EA of P,S,Cl is more than N,O,F respectively. I want to arrange them in order of their EA2 ...
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electron affinities of Be and Ca

I have found in the textbook that Be has negative electron affinity while Ca has positive why? how can I compare the electron affinity values of these two.?
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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 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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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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Can we add an electron to an atom?

Say that we have an atom which is inert, or stable. How would one go about adding one electron. Is it possible?
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List in order of increasing radius

List in order of increasing radius: a) Rb, K, C5, Kr For this one I got C, Kr, K, Rb b) Ar, Cs, Si, Al This I got: Ar, Si, Al, Cs Does anyone know if this is correct? I don't have the solution ...
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Order of basicity of halides [duplicate]

The order of basicity of halides is $\ce{F- >Cl- > Br- > I-}$ My teacher explained this on the basis that the smaller is the ion, the greater is the charge/size ratio, hence it more ...
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Second electron affinity of sulfur and oxygen

Why is the second electron affinity of oxygen greater than that of sulfur? I think it should be like- second electron gain enthalpy of oxygen should be greater than the sulfur but electron affinity ...
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Electron Gain Enthalpy of Noble Gases

Why does He(helium) has less positive electron gain enthalpy than Neon(Ne). The size of atoms increase down the zero group and also the effective nuclear charge increase down the group. Therefore the ...