Ionization Energy and Electron Affinity

Q. Out of the following two coordination entities which is chiral (optically active)?

$A)$ $cis-\left[CrC{l}_2\right(ox{)}_2{]}^{3-}$

$B)$ $trans-\left[CrC{l}_2\right(ox{)}_2{]}^{3-}$

Q. The first and the second ionisation energies of magnesium are 7.646 eV and 15.035 eV respectively. The amount of energy in kJ needed to convert all the atoms of magnesium into $M{g}^{2+}$ ions present in 24 mg of magnesium vapour will be:
(Given $1eV=96.5kJmo{l}^{–1}$).

1. $2.455kJ$
2. $2.188kJ$
3. $1.094kJ$
4. $4.370kJ$

Q.

Chlorine is an element of atomic number 17. It is a mixture of two isotopes having mass number of 35 and 37.

(i) What is meant by “atomic number of an element” ?

(ii) Write down the electronic configuration of the Chlorine atom.

(iii) State the number of protons, electrons and neutrons in the following isotopes : ${}_{17}{}^{35}\mathrm{Cl}$ & ${}_{17}{}^{37}\mathrm{Cl}$

(iv) Explain why the two atoms in ${}_{17}{}^{35}\mathrm{Cl}$ & ${}_{17}{}^{37}\mathrm{Cl}$ have the same chemical reactions.

Q. Fill in the blank
Formation of a compound through ionic bond _____ the ionization energy of the metal ion.

1. Depend on
2. May or may not depend on
3. Does not depends on
4. Is independent regarding

Q. Which of the following pairs show opposite trend on moving along a period from left to right and from top to bottom in a group ?

1. Ionization enthalpy and electron gain enthalpy (negative value)
2. None of the above
3. Nuclear charge and ionization enthalpy
4. Atomic radius and electron gain enthalpy (negative value)

Q. Ionization potential and electron affinity of fluorine are $17.42$ and $3.45eV$ respectively. The electronegativity of fluorine on Mulliken scale and Pauling scale is $x$ & $y$ respectively, then $\frac{(x+y)}{1.011}$is:

1. 13
2. 14
3. 15
4. 12

Q. If $x,y\text{and}z$ are electronegativity, ionisation potential and electron-affinity respectively. Then the electron affinity $\left(z\right)$ in the terms of electronegativity $\left(x\right)$ and ionisation potential $\left(y\right)$ will be:

1. $z=\frac{x+y}{z}$
2. $z=\frac{x-y}{z}$
3. $z=\frac{x^2-y^2}{z}$
4. $z=2x-y$

Q. Why is IE of O less than N?

Q. How many Faradays are required to reduce $1mol$ $Br{O}_3^{-}$ to $B{r}^{-}$ ?

1. 6
2. 5
3. 4
4. 3

Q. $C{u}^{+}$ ion is not stable in aqueous solution because:

1. second ionisation enthalpy of copper is less than the first ionisation enthalpy
2. large value of second ionisation enthalpy of copper is compensated by much more negative hydration energy of $C{u}_{\left(aq\right)}^{2+}$
3. hydration energy of $C{u}_{\left(aq\right)}^{2+}$ is much more negative than that of $C{u}_{\left(aq\right)}^{2+}$
4. many copper (I) compounds are unstable in aqueous solution and undergo a disproportionation reaction

Q. There are four elements p, q , r and s having atomic number $Z-1,Z,Z+1,Z+2$ respectively. If the element q is an inert gas, select the correct statements from following statements:
(i) p has most negative electron gain enthalpy in the respective period
(ii) r is an alkali metal
(iii) s exists in +2 oxidation states

1. (i) and (ii) only
2. (ii) and (iii) only
3. (i) and (iii) only
4. (i), (ii) and (iii)

Q. The electron gain enthalpy (in kJ/mol) of Fluorine, Chlorine, Bromine and Iodine, respectively, are:

1. $-333,-325,-349\text{and}-296$
2. $-349,-333,-325\text{and}-296$
3. $-333,-349,-325\text{and}-296$
4. $-296,-325,-333\text{and}-349$

Q.

Arrange the following in increasing order of the atomic sizes and give reasons

Na⁺ , Mg²⁺ , Al³⁺ , F^- , O^2- , C^4-

Q.

Fill in the blanks from the choices given below:

(1) Across a period, the ionization potential ……. (increases/decreases/remains the same).

(2) Down the group, electron affinity……. (increase/decreases/remains the same).

Q. In ${\left({NH}_4\right)}_2{SO}_4$, acidic and basic radicals are :

1. ${NH}_4^{+}$ and ${SO}_4^{2-}$
2. ${SO}_4^{2-}$ and ${NH}_4^{+}$
3. Both A and B
4. None of the above

Q.

Which one of the following is the biggest ion

[MP PET

1. Al ⁺³

2. Ba⁺²

3. Mg⁺²

4. Na⁺

Q.

Oxygen (at. no. 8) and sulphur (at. no. 16) belong to same group of the periodic table.

(a) State the electronic configuration of:

1. Oxygen
2. Sulphur

(b) Name the group in which these elements belong.

Q.

How does atomic radius vary in a period and in a group? How do you explain the variation?

Q. ntHenrys constant for argon is 40k bar in water , determine Molal concentration of argon in watwr when it is stored above water at 10bar pressuren

Q. Which of the following isoelectronic ions have lowest ionization?

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

Q. Select the correct statement (s):

1. The value of electron gain enthalpy of an element can be negative or positive
2. Metallic charecter of the elements increases down the group and decreases across the period
3. Ionization enthalpy of an atom is equal to electron gain enthalpy of it's unipositive cation in terms of magnitude.
4. The $C{l}^{-}$ and $C{a}^{2+}$ are iso- electronic species but first has larger size than second

Q. Ionization potential and electron affinity of fluorine are $17.42$ and $3.45eV$ respectively. The electronegativity of fluorine on Mulliken scale and Pauling scale is $x$ & $y$ respectively, then $\frac{(x+y)}{1.011}$is:

1. 15
2. 13
3. 12
4. 14

Q.

what is ionisation potential

Q. The ionization potential of ithium is 520 KJ/ mole .The energy required to convert 70 mg of lithum atoms in gaseous state into $L{i}^{+}$ ions is ______________.

1. 52 KJ
2. 5.2 KJ
3. 520 KJ
4. 52 J

Q. First and second ionization energies of magnesium are $7$ and $15\text{eV}$ respectively. The amount of energy in ${\text{kJ mol}}^{-1}$ needed to convert all the atoms of Magnesium into $M{g}^{2+}$ ions present in $12\text{mg}$ of magnesium vapours is: (Report your answer upto two decimal)
[Given: $1\text{eV}=96.5{\text{kJ mol}}^{-1}]$

Q. Order of negative electron gain enthalpy of group 16 elements

Q. There are four elements p, q , r and s having atomic number $Z-1,Z,Z+1,Z+2$ respectively. If the element q is an inert gas, select the correct statements from following statements:
(i) p has most negative electron gain enthalpy in the respective period
(ii) r is an alkali metal
(iii) s exists in +2 oxidation states

1. (i) and (ii) only
2. (ii) and (iii) only
3. (i) and (iii) only
4. (i), (ii) and (iii)

Q. why electron gain enthalpy of He the least positive amongst noble gases

Q. Identify the optically active compounds from the following:

1. $cis–\left[Co\right(en{)}_{2}C{l}_2{]}^{+}$
   
2. $trans–\left[Co\right(en{)}_{2}C{l}_2{]}^{+}$
   
3. $\left[Co\right(en{)}_3{]}^{3+}$
4. $\left[Cr\right(N{H}_3{)}_{5}Cl]$

Q.

Which set of elememel shows positive electron gain enthalpy?

1. He, N, O

2. Ne, N, Cl

3. O, Cl, F

4. N, He, Ne