d- and f-Block Elements

Which of the following sets includes all the species that will change the orange colour of $\ce{K2Cr2O7}$ in acidic medium ?

Given below are two statements :

Statement I : Among Zn, Mn, Sc and Cu, the energy required to remove the third valence electron is highest for Zn and lowest for Sc.

Statement II : The correct order of the following complexes in terms of CFSE is $\ce{[Co(H2O)6]^{2+}} < \ce{[Co(H2O)6]^{3+}} < \ce{[Co(en)3]^{3+}}$.

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

Among $\ce{Fe^{2+}}$, $\ce{Fe^{3+}}$, $\ce{Cr^{2+}}$ and $\ce{Zn^{2+}}$, the ion that shows positive borax bead test and with highest ionisation enthalpy is :

Number of paramagnetic ions among the following d- and f-block metal ions is ________.
$\ce{Mn^{2+}}$, $\ce{Cu^{2+}}$, $\ce{Zn^{2+}}$, $\ce{Yb^{2+}}$, $\ce{Sc^{3+}}$, $\ce{La^{3+}}$, $\ce{Gd^{3+}}$, $\ce{Lu^{3+}}$, $\ce{Ti^{4+}}$, $\ce{Ce^{4+}}$
(Atomic number of Mn = 25, Cu = 29, Zn = 30, Yb = 70, Sc = 21, La = 57, Gd = 64, Lu = 71, Ti = 22, Ce = 58)

In order to oxidise a mixture of 1 mole each of $\ce{FeC2O4}$, $\ce{Fe2(C2O4)3}$, $\ce{FeSO4}$ and $\ce{Fe2(SO4)3}$ in acidic medium, the number of moles of $\ce{KMnO4}$ required is

The correct statements among the following are,

A. Mo(VI) and W(VI) are less stable than Cr(VI).

B. $\ce{Ce^{4+}}$ and $\ce{Tb^{4+}}$ are oxidant while $\ce{Eu^{2+}}$ and $\ce{Yb^{2+}}$ are reductant.

C. Cm and Am have seven unpaired electrons.

D. Actinoid contraction is greater from element to element than lanthanoid contraction.

Choose the correct answer from the options given below:

Correct statements from the following are

A. Potassium dichromate is an oxidising agent and it oxidises $\ce{FeSO4}$ to $\ce{Fe2(SO4)3}$ in acidic medium.

B. Sodium dichromate can be used as primary standard in volumetric estimation.

C. $\ce{CrO4^{2-}}$ and $\ce{Cr2O7^{2-}}$ are interconvertible in aqueous solution by varying the pH of the solution.

D. Cr-O-Cr bond angle in $\ce{Cr2O7^{2-}}$ is 126°.

Choose the correct answer from the options given below:

Pairs of elements with the same number of electrons in their respective 4f orbital are

[Atomic number. Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72]

A. (Eu and Gd)

B. (Dy and Ho)

C. (Yb and Hf)

D. (Lu and Tm)

Choose the correct answer from the options given below:

Consider $|x|$ is the difference in oxidation states of Mn in highest manganese fluoride and highest manganese oxide. The ions with $|x|$ number of unpaired electrons from the following are:

A. $\ce{Sc^{3+}}$

B. $\ce{Zn^{2+}}$

C. $\ce{V^{2+}}$

D. $\ce{Fe^{2+}}$

E. $\ce{Co^{2+}}$

Choose the correct answer from the options given below:

Among $\ce{Fe^{3+}}$, $\ce{Pb^{2+}}$, $\ce{Cu^{2+}}$ and $\ce{Mn^{2+}}$, identify the one that gets precipitated out while passing $\ce{H2S}$ in presence of $\ce{NH4OH}$ as group reagent. The highest possible oxidation state of the corresponding metal is

Which of the following is NOT a physical or chemical characteristics of interstitial compounds?

Given below are two statements:

Statement I: Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis.

Statement II: Phenolphthalein is a weak base, therefore it dissociates in acidic medium.

In the light of the above statements, choose the correct answer from the options given below

Given below are two statements :

Statement I: Presence of large number of unpaired electrons in transition metal atoms results in higher enthalpies of their atomisation.

Statement II: $d_{xy}=d_{xz}=d_{yz}<d_{x^2-y^2}=d_{z^2}$ and $d_{x^2-y^2}=d_{z^2}<d_{xy}=d_{xz}=d_{yz}$ are the d-orbital splittings in $\ce{[Fe(H2O)6]^3+}$ and $\ce{[NiCl4]^2-}$ complex ions respectively.

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

A paper dipped in a dil. $\ce{H2SO4}$ solution of 'X' upon treatment with $\ce{SO2}$ gas turns into green. The compound 'X' is :

The correct statements among the following are.

A. Basic vanadium oxide is used in the manufacture of $\ce{H2SO4}$.

B. The spin-only magnetic moment value of the transition metal halide employed in Ziegler-Natta polymerization is 2.84 BM.

C. The p-block metal compound employed in Ziegler-Natta polymerization has the metal in +3 oxidation state.

D. The number of electrons present in the outer most 'd' orbital of metal halide employed in Wacker process is 8.

Choose the correct answer from the options given below:

The correct order of first ($\Delta_iH_1$) and second ($\Delta_iH_2$) ionisation enthalpy values of Cr and Mn are :

A. $\Delta_iH_1$ : Cr > Mn

B. $\Delta_iH_2$ : Cr > Mn

C. $\Delta_iH_1$ : Mn > Cr

D. $\Delta_iH_2$ : Mn > Cr

Choose the correct answer from the options given below :

Given below are two statements :

Statement I : The number of pairs among $[\ce{Ti^4+},\ \ce{V^2+}]$, $[\ce{V^2+},\ \ce{Mn^2+}]$, $[\ce{Mn^2+},\ \ce{Fe^3+}]$ and $[\ce{V^2+},\ \ce{Cr^2+}]$ in which both ions are coloured is 3.

Statement II : The number of pairs among $[\ce{La^3+},\ \ce{Yb^2+}]$, $[\ce{Lu^3+},\ \ce{Ce^4+}]$ and $[\ce{Ac^3+},\ \ce{Lr^3+}]$ ions in which both are diamagnetic is 3.

In the light of the above statements, choose the correct from the options given below :

Given below are two statements for catalytic properties of transition metals.

Statement I : First row transition metals which act as catalyst utilise their 3d electrons only for formation of bonds between reactant molecules and atoms on the surface of catalyst.

Statement II : There is increase in the concentration of reactants on the surface of catalyst which strengthens the bonds in reacting molecules.

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

One of the products formed from the reaction of permanganate ion with iodide ion in neutral aqueous medium is

The pair(s) of diamagnetic ions is(are)