The d- and f-Block Elements PYQs

Match List-I with List-II: Choose the correct answer from the options given below.

Although +3 oxidation state is most common in lanthanoids, cerium still shows +4 oxidation state because:

The calculated spin-only magnetic moment of Ti²⁺ (3d²) is:

Which among the following electronic configurations belong to main group elements? A. [Ne]3s¹ B. [Ar]3d³4s² C. [Kr]4d¹⁰5s²5p⁵ D. [Ar]3d¹⁰4s¹ E. [Rn]5f⁰6d²7s² Choose the correct answer from the options given below.

Given below are two statements : Statement I : Ferromagnetism is considered as an extreme form of paramagnetism. Statement II : The number of unpaired electrons in a Cr²⁺ ion (Z = 24) is the same as that of a Nd³⁺ ion (Z = 60). In the light of the above statements, choose the correct answer from the options given below :

Match List - I with List - II Choose the correct answer from the options given below :

‘Spin only’ magnetic moment is same for which of the following ions? A. $\mathrm{Ti^{3+}}$ B. $\mathrm{Cr^{2+}}$ C. $\mathrm{Mn^{2+}}$ D. $\mathrm{Fe^{2+}}$ E. $\mathrm{Sc^{3+}}$ Choose the most appropriate answer from the options given below:

The E° value for the Mn³⁺/Mn²⁺ couple is more positive than that of Cr³⁺/Cr²⁺ or Fe³⁺/Fe²⁺ due to change of:

The stability of Cu²⁺ is more than Cu⁺ salts in aqueous solution due to:

Taking stability as the factor, which one of the following represents correct relationship?

Which of the following statements are INCORRECT? A. All the transition metals except scandium form MO oxides which are ionic. B. The highest oxidation number corresponding to the group number in transition metal oxides is attained in Sc₂O₃ to Mn₂O₇. C. Basic character increases from V₂O₃ to V₂O₄ to V₂O₅. D. V₂O₄ dissolves in acids to give VO₄³⁻ salts. E. CrO is basic but Cr₂O₃ is amphoteric. Choose the correct answer from the options given below :

Gadolinium has a low value of third ionisation enthalpy because of:

In the neutral or faintly alkaline medium, KMnO₄ oxidises iodide into iodate. The change in oxidation state of manganese in this reaction is from:

Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of:

The incorrect statement among the following is:

The calculated spin only magnetic moment of Cr²⁺ ion is

Identify the incorrect statement.

When neutral or faintly alkaline $KMnO_4$ is treated with potassium iodide, iodide ion is converted into ‘X’. ‘X’ is

The oxidation state of Cr in $CrO_6$ is:

Formula of nickel oxide with metal deficiency defect in crystal is $Ni_{0.98}O$. The crystal contains $Ni^{2+}$ and $Ni^{3+}$ ions. The fraction of nickel existing as $Ni^{2+}$ ions in the crystal is:

Which one of the following statements related to lanthanoids is incorrect?

Gadolinium belongs to 4f series. Its atomic number is 64. Which of the following is the correct electronic configuration of gadolinium?

In acidic medium, H₂O₂ changes Cr₂O₇²⁻ to CrO₅, which has two (−O−O−) bonds. Oxidation state of Cr in CrO₅ is:

Among the following complexes, the one which shows zero crystal field stabilization energy (CFSE) is:

Magnetic moment 2.83 BM is given by which of the following ions? (Atomic numbers: Ti = 22, Cr = 24, Mn = 25, Ni = 28)

Reason of lanthanoid contraction is:

$KMnO_4$ can be prepared from $K_2MnO_4$ as per the reaction: $$3MnO_4^{2-}+2H_2O \rightleftharpoons 2MnO_4^-+MnO_2+4OH^-$$ The reaction can go to completion by removing OH⁻ ions by adding

The catalytic activity of transition metals and their compounds is ascribed mainly to:

Which one of the following does not correctly represent the order of the property indicated against it?

Which of the following exhibits only +3 oxidation state?

Which of the following oxidation state is the most common among the lanthanoids?

Which one of the elements with the following outer orbital configurations may exhibit the largest number of oxidation states?

Why is CrO₄²⁻ a stronger oxidizing agent than MoO₄²⁻?

More number of oxidation states are exhibited by the actinoids than by the lanthanoids. The main reason for this is:

In which of the following pairs are both the ions coloured in aqueous solution? (At. no.: Sc = 21, Ti = 22, Ni = 28, Cu = 29, Co = 27)

The aqueous solution containing which one of the following ions will be colourless? (Atomic no.: $Sc = 21$, $Fe = 26$, $Ti = 22$, $Mn = 25$)