Electron Gain Enthalpy

Q.

Why is the electronegativity of oxygen greater than that of carbon?

Q. Which of the following processes involves absorption of energy?

1. $Cl\left(g\right)+e^{-}\to C{l}^{-}\left(g\right)$
2. $O^{-}\left(g\right)+e^{-}\to O^{2-}\left(g\right)$
3. $O\left(g\right)+e^{-}\to O^{-}\left(g\right)$
4. $S\left(g\right)+e^{-}\to S^{-}\left(g\right)$

Q. Which of the following species has the negative electron gain enthalpy?

1. $F^{-}$
2. $O$
3. $O^{2-}$
4. $N{a}^{+}$

Q. The compound $X^{+}{Y}^{-}$ is formed when:

1. Electron affinity of Y is low and ionisation energy of X is high
2. Electron affinity of Y is high and ionisation energy of X is low
3. Both electron affinity of Y and ionisation energy of X is high
4. Both electron affinity of Y and ionisation energy of X is low

Q.

The ionization energy of $F^{-}$ is 320 kJ/mole. The electron gain enthalpy of fluorine would be?

1. -320 kJ/mole

2. -160 kJ/mole

3. 320 kJ/mole

4. 160 kJ/mole

Q.

In which of the following processes is energy liberated?

1. Cl = $C{l}^{+}$ + $e^{-}$

2. HCl =$H^{+}$ + $C{l}^{-}$

3. Cl + $e^{-}$= $C{l}^{-}$

4. $O^{-}$ + $e^{-}$ = $O^{-2}$

Q. Ionisation of energy of $F^{-}$ is $320{\text{kJ mol}}^{-1}$. The electron gain enthalpy of fluorine would be

1. $-320{\text{kJ mol}}^{-1}$
2. $-160{\text{kJ mol}}^{-1}$
3. $+320{\text{kJ mol}}^{-1}$
4. $160{\text{kJ mol}}^{-1}$

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. Which one of the following is incorrect?

1. An element which has high electronegativity always has high electron gain enthalpy
2. Electron gain enthalpy is the property of a bonded atom
3. Electronegativity is the property of a bonded atom
4. Both electronegativity and electron gain enthalpy are usually directly related to nuclear charge and inversely related to atomic size.

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. 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. The process that requires an absorption of energy is:

1. $F\to F^{-}$
2. $H\to H^{-}$
3. $Cl\to C{l}^{-}$
4. $O\to O^{2-}$

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. 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.

Electron gain enthalpy depends on:

1. Atomic size

2. Number of neutrons

3. Atomic weight

4. Nuclear charge

Q. For the gaseous reaction: $K\left(g\right)+F\left(g\right)\to K^{+}\left(g\right)+F^{-}\left(g\right),$ $\Delta H$ was calculated to be $91.4\text{kJ/mol}$ under conditions where the cations and anions were prevented from combining with each other. The ionisation enthalpy of $K$ is $418\text{kJ/mol}$. What is the electron gain enthalpy $\left(\text{in kcal/mol}\right)$ of $F?$

1. -78.13
2. -326.6
3. 326.6
4. 78.13

Q. Which of the following statements is correct?

1. The elements having large negative values of electron gain enthalpy generally act as strong oxidising agents
2. The elements having low values of ionisation enthalpy act as strong reducing agents
3. The formation of $S^{2-}\left(g\right)$ from $S\left(g\right)$ is an endothermic process
4. All of these

Q. Which of the following is/are correct ?

1. An element which has higher electronegativity always has a higher electron gain enthalpy
2. Electron gain enthalpy is the property of an isolated atom
   
3. Electronegativity is the property of a bonded atom
   
4. Both electronegativity and electron gain enthalpy are usually directly related to nuclear charge and inversely related to atomic size

Q.

For the processes $K^{+}\left(g\right)\stackrel{I}{⟶}K\left(g\right)\stackrel{II}{⟶}{K}^{-}\left(g\right)$

1. Energy is released in (I) and absorbed in (II)

2. Energy is absorbed in (I) and released in (II)

3. Energy is absorbed in both the processes

4. Energy is released in both the processes

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. S > Se > O
4. O > Se > S

Q.

If one electron has been removed from an atom, it becomes increasingly difficult to remove the second and subsequent electrons from the resulting positively charged ions on account of electrostatic attraction.
The numerical value of energy involved in the given process $K\to K^{-}$ is less than that of which of the following processes?

1. $K^{-}\to K$

2. $K\to K^{+}$

3. Both (a) and (b)

4. None of these

Q. Consider the following reactions :
$O_{\left(g\right)}+e^{-}\to O_{\left(g\right)}^{-},\Delta H_1$
$F_{\left(g\right)}+e^{-}\to F_{\left(g\right)}^{-},\Delta H_2$
$C{l}_{\left(g\right)}+e^{-}\to C{l}_{\left(g\right)}^{-},\Delta H_3$
$O_{\left(g\right)}^{-}+e^{-}\to O_{\left(g\right)}^{2-},\Delta H_4$
The correct statement(s) is/are

1. $\Delta H_3$ and $\Delta H_2$ both are negative
2. $\Delta H_1$ and $\Delta H_4$ both are positive
3. $\Delta H_1$, $\Delta H_2$ and $\Delta H_3$ are negative
4. $\Delta H_4$ is negative