Ionization Energies

Q. How many unpaired electrons are present in the Brown Ring complex [Fe(H2O)5(NO)]SO4- (1) 4 (2) 3 (3) 0 (4) 5

Q. The atomic numbers of V, Cr, Mn and Fe are 23, 24, 25 and 26 respectively. Which one of these may be expected to have the highest second ionization enthalpy?

1. Fe
2. V
3. Mn
4. Cr

Q. The first ionization enthalpies of 5d elements is higher than that of the corresponding 3d and 4d elements. This is best explained by:

1. Greater extent of metallic bonding in 5d elements
2. Neither a nor b
3. Greater effective nuclear charge in the case of 5d elements due to the poor shielding of valence electrons by the 4f electrons
4. Both a and b

Q. Which of the following element has maximum first ionisation potential

1. Ti
2. Cr
3. Mn
4. V

Q. Which of the following atoms has the highest first ionization energy?

1. $Na$
2. $K$
3. $Sc$
4. $Rb$

Q. Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionization enthalpy?

1. Vanadium (Z = 23)
2. Chromium (Z = 24)
3. Manganese (Z = 25)
4. Iron (Z = 26)

Q. The atomic number of vanadium (V), chromium (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24, 25 and 26 which one of these may be expected to have the highest second ionization enthalpy

1. Cr
2. Mn
3. Fe
4. V

Q. Select the correct answer-
(i) Across a period, the ionization potential _______ [increases, decreases, remains same]

Q.

If successive ionization energies of an element are 7.9 ev, 13.2 ev and 247.8 ev respectively, the element is expected to be?

Q. Which of the following has $2^{nd}$ Ionisation Potential less than excepted

1. Cr
2. Zn
3. V
4. Mo

Q. The maximum number of electrons present in an atom whose highest principal quantum no. is 4 is 32 How?

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Q. The correct order of decreasing first ionisation energy is:

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

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:

(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)If assertion is true but reason is false.

(d)If assertion is false but reason is true.
Assertion: Ionisation enthalpies for early actinoids are lower than that for early lanthanoids.
Reason: 5f electrons more effectively shielded from the nuclear charge than the 4f electrons
of the corresponding lanthanoids.

1. a
2. b
3. c
4. d

Q.

What happens when ionization energy increases?

Q.

Predict the formula of the stable binary compounds that would be formed by the combination of the following pairs of elements.

(a) Lithium and oxygen (b) Magnesium and nitrogen

(c) Aluminium and iodine (d) Silicon and oxygen

(e) Phosphorus and fluorine (f) Element 71 and fluorine

Q. Which of the following does not obey EAN (Effective Atomic Number) rule?

1. $Fe(CO{)}_5$
2. $K_4\left[Fe\right(CN{)}_6]$
3. $\left[Cu\right(N{H}_3{)}_4]S{O}_4$
4. $\left[Co\right(N{H}_3{)}_6]C{l}_3$

Q. Give the reasons for the following :

(iii) Ionization potential of the element increases across a period.

Q. Beryllium differs in properties from other elements of its own group but shows resemblance with aluminium because of:

1. relatively smaller ionic radius and high polarising power of $Be$
2. relatively bigger ionic radius is the only reason behind this
3. relatively bigger ionic radius and high polarising power of $Be$
4. none of the above

Q. If the ionisation potential of an atom is 20V, its first excitation potetial will bw ( 1)5 (2) 10 (3) 15 (4) 20

Q. Among the triatomic molecules/ions, $BeC{l}_2,{N_3}^{-},N_{2}O,N{O}_2^{+},O_3,SC{l}_2,{IC{l}_2}^{-},{I_3}^{-}$ and $Xe{F}_2,$ the total number of linear molecule(s)/ion(s) where the hybridization of the central atom does not have contribution from the d-orbital(s) is

Q. The atomic number of $V,Cr,Mn$ and $Fe$ are $23,24,25$ and $26$ respectively. Which one of these may be expected to have the highest second ionisation enthalpy?

1. $V$
2. $Cr$
3. $Mn$
4. $Fe$

Q. While converting $Ce$ to $C{e}^{3+}$, which process requires highest ionization energy?

1. $Ce$ to $C{e}^{+}$
   
2. $C{e}^{+}$ to $C{e}^{3+}$
   
3. Both A and B require the same amount of energy.
4. None of the above

Q. Ionisation enthalpy/$KJmo{l}^{-1}:520,899,801,1086,1402,1314,1681,2080$.

Q. The ability of $d$-block elements to form complexes is due to:

1. low polarizing power of cation
2. small and highly charged ions
3. vacant low energy orbitals to accept lone pair of electrons from ligands
4. none is correct

Q.

Q. A tetrahedral $d^6$ ion ( high spin):

Q. Which of the following compounds is/are expected to be colored?

1. $Ti(N{O}_3{)}_4$
2. $\left[Cu\right(NCC{H}_3{)}_4]B{F}_4^{-}$
3. $\left[Cr\right(N{H}_3{)}_6{]}^{3+}+3C{l}^{-}$
4. $K_3\left[V{F}_6\right]$

Q. Assertion :The third ionization energy of manganese (At no. 25) unexpectedly high. Reason: Loss of two electrons gives the configuration of $M{n}^{2+}$ as; [Ar]$3d^5$ where d-orbital is half filled and thus, very stable.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Why is ionization enthalpy of Beryllium higher than Boron.

Q. "$LiCl$ is covalent while $NaCl$ is ionic."
Answer whether the above statement is true or false.
If true enter 1, else enter 0.