Electron Gain Enthalpy

Q.

What is the difference between bonding and antibonding molecular orbitals?

Q.

Increasing order of electron gain enthalpy of the group $16$ is:

Q.

Which of the following represents correct order of increasing electron gain enthalpy with negative sign for the elements 0, S, F and Cl? [CBSE AIPMT 2010]

1. CI< F< O< S

2. O< S< F< CI

3. F< S< O< CI

4. S< O< CI< F

Q.

An electron, a doubly ionized helium ion (${\mathrm{He}}^{2+}$) and a proton are having the same kinetic energy. The relation between their respective de-Broglie wavelengths ${\mathrm{\lambda }}_{\mathrm{e}}$, ${\mathrm{\lambda }}_{{\mathrm{He}}^{2+}}$ and ${\mathrm{\lambda }}_{\mathrm{p}}$ is

1. ${\mathrm{\lambda }}_{\mathrm{e}}$ $>$ ${\mathrm{\lambda }}_{\mathrm{p}}$ $>$ ${\mathrm{\lambda }}_{{\mathrm{He}}^{++}}$

2. ${\mathrm{\lambda }}_{\mathrm{e}}$ $>$ ${\mathrm{\lambda }}_{{\mathrm{He}}^{++}}$$>$ ${\mathrm{\lambda }}_{\mathrm{p}}$

3. ${\mathrm{\lambda }}_{\mathrm{e}}$ $<$ ${\mathrm{\lambda }}_{\mathrm{p}}$ $<$ ${\mathrm{\lambda }}_{{\mathrm{He}}^{++}}$

4. ${\mathrm{\lambda }}_{\mathrm{e}}$ $<$ ${\mathrm{\lambda }}_{{\mathrm{He}}^{++}}$ $=$ ${\mathrm{\lambda }}_{\mathrm{p}}$

Q.

Which of the following pairs of elements would have a more negative electron gain enthalpy?
(i) O or F

(ii) F or Cl

Q.

The radius of the nucleus of an atom is approximately equal to _______

Q.

Why $PC{l}_5$ exist but not $NC{l}_5$

Q. The correct order of magnitude of electron gain enthalpy of $O,S$ and $Se$ is:

1. O > S > Se
2. S > O > Se
3. O > Se > S
4. S > Se > O

Q.

In the following question a statement of assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the choices given below in each question.
Assertion (A) Electron gain enthalpy becomes less negative as we go down a group.
Reason. (R) size fo the atom inscreses on going down the group and the added electron would be farther from the nucleus.
(a) Assertion and reason both are correct statement but reason is not correct explanation for assertion.
(b) assertion and reason both are correct statements and reason is correct explanation for assertion .
(c) Assertion and reason both are wrong statements.
(d) Assertion is wrong statement but reason is correct statement.

Q.

Would you expect the second electron gain enthalpy of O as positive, more negative or less negative than the first? Justify your answer.

Q. Given below are two statements : one is labelled as
Assertion (A) and the other is labelled as
Reason (R).

Assertion (A) : Metallic character decreases and non-metallic character increases on moving from left to right in a period.

Reason (R) : It is due to increase in ionisation enthalpy and decrease in electron gain enthalpy, when one moves from left to right in a period.

In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both (A) and (R) are correct and (R) is the correct explanation of (A)
2. (A) is true but (R) is false
3. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
4. (A) is false but (R) is true

Q. The electron gain enthalpies of halogens in $kJmo{l}^{-1}$ are as given below:
F = $-332$, Cl = $-349$, Br = $-324$, I = $-295$.
The less negative value for F as compared to that of CI is due to:

1. Strong electron-electron repulsion in the compact 2p- sub shell of F.
2. Weak electron - electron repulsion in the bigger 3p- sub shell of Cl
3. Smaller electronegativity value of F than Cl
4. (A) and (B) both

Q.

Out of the three isotopes of hydrogen which is more electronegitive and why ?

Q.

How to calculate bond order of superoxide?

Q. Statement 1: $F$ atom has a less negative electron gain enthalpy than $Cl$ atom.
Statement 2: Additional electron is repelled more efficiently by $3p$ electron in $Cl$ atom than by $2p$ electron in $F$ atom.

1. Statement 1 is true and statement 2 is false
2. None of the statements are true
3. Both the statements are correct and statement 2 is the correct explanation of statement 1
4. Both the statements are correct and statement 2 is not the correct explanation of statement 1

Q.

Why cu is smaller when compared to na?

Q.

Electronic configuration of four elements A, B, C, and D are given below
A. $1s^{2}2s^{2}2p^6$ B. $1s^{2}2s^{2}2p^4$ C. $1s^{2}2s^{2}2p^{6}3s^1$
D. $1s^{2}2s^{2}2p^5$
Whilch of the following is the correct order of increasing tendency to gain electron?
(a) A < C <B <D (b) A < B < C < D (c) D <B < C < A (d) D < A < B <C

Q. Although fluorine is more electronegative than oxygen, but the ability of oxygen to stabilize higher oxidation states exceeds that of fluorine. Why?

Q.

Discuss the factors affecting electron gain enthalpy and the trend in its variation in the periodic table.

Q. Assertion: Linkage isomerism arises in coordination compounds containing ambidentate ligand.

Reason: Ambidentate ligand has two different donor atoms.

1. Assertion is false, reason is true.
   
2. Assertion is true, reason is false.
   
3. Assertion and reason both are true, reason is correct explanation of assertion.
   

4. Assertion and reason both are true but reason is not the correct explanation of assertion.

Q. Which among the following elements will have a positive electron gain enthalpy?

1. $B$
2. $C$
3. $N$
4. $O$

Q. The amount of energy released when ${10}^{12}$ atoms of $Cl$ (vapour) are converted to $C{l}^{-}$ ions, according to the equation:
$C{l}_{\left(g\right)}+e^{-}\to C{l}_{\left(g\right)}^{-}\text{is}58\times {10}^{-10}\text{J}$
Calculate the ${\Delta }_{eg}{H}^{-}$ of $Cl$ atom in ${\text{eV atom}}^{-1}$.

1. $-0.036{\text{eV atom}}^{-1}$
2. $-3.480{\text{eV atom}}^{-1}$
3. $+0.038{\text{eV atom}}^{-1}$
4. $-0.361{\text{eV atom}}^{-1}$

Q. For a metallic crystal, which band do the delocalized electrons occupy?

1. Conduction band
2. Valence band
3. Both, conduction and valence bands
4. There are no delocalized electrons

Q.

Draw the electron dot structure of the hydroxyl ion.

Q. The incorrect statement is

1. In manganate and permanganate ions. the $\pi$-bonding takes place by overlap of p-orbitals of oxygen and d-orbitals of manganese
2. Manganate ion is green in colour and permanganate ion is purple in colour
   
3. Manganate and permanganate ions are paramagnetic
4. Manganate and permanganate ions are tetrahedral

Q. Polymer formation from monomers starts by:

1. Condensation reaction between monomers
2. Substitution reaction between monomers
3. Conversion of monomer to monomer ions by protons
4. Hydrolysis of monomers

Q. The first ionization energy of magnesium is smaller as compared to that of elements X and Y but higher than that of Z. The elements X, Y and Z, respectively are:

1. argon, lithium and sodium
2. chlorine, lithium and sodium
3. neon, sodium and chlorine
4. argon, chlorine and sodium

Q.

Which of the following elements fwill gain one electron more readily in comparison to other elements of their group?
(a) S(g) (b) Na (g) (c) O (g) (d) Cl(g)

Q.

Electronic configuration of some elements is given in colum I and their electron gain enethalpies are given in Column II mathc the electronic configuration with electron gain enthalpy
$$\begin{array}{cc}\underset{\left(Electronicconfiguration\right)}{ColumnI}& \underset{Electrongainenthalpy/KJmo{l}^{-1}}{ColumnII}\\ A.1s^{2}2s^{2}2p^6& -53\\ B.1s^2,2s^2,2p^6,3s^1& -328\\ C.1s^2,2s^2,2p^5& -141\\ D.1s^2,2s^2,2p^4& +48\end{array}$$

Q. The correct order of electron gain enthalpy (from most to least endothermic) is:

1. $Be>C>B>N$
2. $N>Be>C>B$
3. $Be>N>B>C$
4. $N>C>B>Be$