Q 11 :

The magnetic moment of transition metal compound has been calculated to be 3.87 B.M. The metal ion is       [2023]

• ${\mathrm{Ti}}^{2+}$

   

• ${\mathrm{Mn}}^{2+}$

   

• ${\mathrm{V}}^{2+}$

   

• ${\mathrm{Cr}}^{2+}$

   

Q 12 :

The set of correct statements is:                               [2023]

(i) Manganese exhibits +7 oxidation state in its oxide.

(ii) Ruthenium and Osmium exhibit +8 oxidation in their oxides.

(iii) Sc shows +4 oxidation state which is oxidizing in nature.

(iv) Cr shows oxidising nature in +6 oxidation state.

• (i) and (iii)

   

• (ii) and (iii)

   

• (i), (ii) and (iv)

   

• (ii), (iii) and (iv)

   

Q 13 :

Given below are two statements:

Statement I: Nickel is being used as the catalyst for producing syn gas and edible fats.

Statement II: Silicon forms both electron rich and electron deficient hydrides.

In the light of the above statements, choose the most appropriate answer from the options given below:          [2023]

• Statement I is incorrect but statement II is correct.

   

• Both the statements I and II are correct.

   

• Statement I is correct but statement II is incorrect.

   

• Both the statement I and II are incorrect.

   

Q 14 :

Highest oxidation state of Mn is exhibited in ${\mathrm{Mn}}_2{\mathrm{O}}_7$. The correct statements about ${\mathrm{Mn}}_2{\mathrm{O}}_7$ are:

(A) Mn is tetrahedrally surrounded by oxygen atoms.

(B) Mn is octahedrally surrounded by oxygen atoms.

(C) Contains Mn–O–Mn bridge.

(D) Contains Mn–Mn bond.

Choose the correct answer from the options given below:              [2023]

• A and D only

   

• A and C only

   

• B and C only

   

• B and D only

   

Q 15 :

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: ${\mathrm{Cu}}^{2+}$ in water is more stable than ${\mathrm{Cu}}^{+}$.

Reason R: Enthalpy of hydration for ${\mathrm{Cu}}^{2+}$ is much less than that of ${\mathrm{Cu}}^{+}$.

In the light of the above statements, choose the correct answer from the options given below:            [2023]

• Both (A) and (R) are correct and (R) is the correct explanation of (A)

   

• (A) is correct but (R) is not correct

   

• Both (A) and (R) are correct but (R) is not the correct explanation of (A)

   

• (A) is not correct but (R) is correct

   

Q 16 :

Which of the following statements are correct?

(A) The ${\mathrm{M}}^{3+}/{\mathrm{M}}^{2+}$ reduction potential for iron is greater than manganese.

(B) The higher oxidation states of first row d-block elements get stabilized by oxide ion.

(C) Aqueous solutions of ${\mathrm{Cr}}^{2+}$ can liberate hydrogen from dilute acid.

(D) Magnetic moment of ${\mathrm{V}}^{2+}$ is observed between 4.4 – 5.2 B.M.

Choose the correct answer from the options given below:                   [2023]

• (A), (B) only

   

• (C), (D) only

   

• (A), (B), (D) only

   

• (B), (C) only

   

Q 17 :

How many of the following metal ions have similar value of spin only magnetic moment in gaseous state? _______

(Given: Atomic number: V, 23; Cr, 24; Fe, 26; Ni, 28)

${\mathrm{V}}^{3+}$, ${\mathrm{Cr}}^{3+}$, ${\mathrm{Fe}}^{2+}$, ${\mathrm{Ni}}^{3+}$                       [2023]

Q 18 :

In ammonium–phosphomolybdate, the oxidation state of Mo is + ________.                       [2023]

Q 19 :

For a metal ion, the calculated magnetic moment is 4.90 BM. This metal ion has ________ number of unpaired electrons.         [2023]

Q 20 :

Find the compound 'A' from the following reaction sequences.

$A\stackrel{\text{aqua-regia}}{\to }B\underset{\text{(2)\hspace{0.05em}AcOH}}{\overset{{\text{(1)\hspace{0.05em}KNO}}_2| {\mathrm{NH}}_4\mathrm{OH}}{\mathit{\to }}}\text{yellow ppt}$                      [2025]

• ZnS

   

• CoS

   

• MnS

   

• NiS

   

Q 21 :

The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is           [2025]

• ${\mathrm{Ti}}^{3+}$
     

• ${\mathrm{Ni}}^{2+}$
     

• ${\mathrm{Mn}}^{2+}$
     

• ${\mathrm{Cr}}^{3+}$

   

Q 22 :

Consider the following elements In, Tl, Al, Pb, Sn and Ge.

The most stable oxidation states of elements with highest and lowest first ionisation enthalpies, respectively, are           [2025]

• +2 and +3

   

• +4 and +3

   

• +4 and +1

   

• +1 and +4

   

Q 23 :

Identify the inorganic sulphides that are yellow in colour :

(A) ${\left({\mathrm{NH}}_4\right)}_2\mathrm{S}$
(B) PbS
(C) CuS
(D) ${\mathrm{As}}_2{\mathrm{S}}_3$
(E) ${\mathrm{As}}_2{\mathrm{S}}_5$

Choose the correct answer from the options given below :              [2025]

• (A) and (C) only

   

• (A), (D) and (E) only

   

• (A) and (B) only

   

• (D) and (E) only

   

Q 24 :

A group 15 element forms $d\pi –d\pi$ bond with transition metals. It also forms hydride, which is a strongest base among the hydrides of other group members that form $d\pi –d\pi$ bond. The atomic number of the element is ____.          [2025]

Q 25 :

The nature of oxide (${\mathrm{TeO}}_2$) and hydride (${\mathrm{TeH}}_2$) formed by Te, respectively are:            [2025]

• Oxidising and acidic

   

• Reducing and basic

   

• Reducing and acidic

   

• Oxidising and basic

   

Q 26 :

A molecule with the formula ${\mathrm{AX}}_2{\mathrm{Y}}_2$ has all its elements from p-block. Element A is rarest, monotomic, non-radioactive from its group and has the lowest ionization energy value among X and Y. Elements X and Y have first and second highest electronegativity values respectively among all the known elements. The shape of the molecule is:     [2025]

• Square pyramidal

   

• Octahedral

   

• Planar

   

• Tetrahedral

   

Q 27 :

Given below are two statements:                                        [2025]

Statement I: The metallic radius of Al is less than that of Ga.

Statement II: The ionic radius of ${\mathrm{Al}}^{3+}$ is less than that of ${\mathrm{Ga}}^{3+}$.

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

• Both Statement I and Statement II are correct

   

• Statement I is correct but Statement II is incorrect

   

• Statement I is incorrect but Statement II is correct

   

• Both Statement I and Statement II are incorrect

   

Q 28 :

"X" is an oxoanion of the lightest element of group 7 (in the periodic table). The metal is in +6 oxidation state in "X". The color of the potassium salt of X is          [2026]

• orange

   

• purple

   

• yellow

   

• green

   

Q 29 :

The oxidation state of chromium in the final product formed in the reaction between $\mathrm{KI}$ and acidified ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ solution is:  [2026]

• +4

   

• +2

   

• +6

   

• +3