jee main chemistry important questions | d And f-Block Elements jee main questions FREE

Q 11 :

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

${Ti}^{2 +}$
${Mn}^{2 +}$
$V^{2 +}$
${Cr}^{2 +}$

1

2

3

4

(3)

Ion	Outer electronic configuration	No. of unpaired electrons	Magnetic moment
${Mn}^{2 +}$	$3 d^{5} 4 s^{0}$	5	$\sqrt{35} BM$
$V^{2 +}$	$3 d^{3} 4 s^{0}$	3	$\sqrt{15} BM$
${Ti}^{2 +}$	$3 d^{2} 4 s^{0}$	2	$\sqrt{8} BM$
${Cr}^{2 +}$	$3 d^{4} 4 s^{0}$	4	$\sqrt{24} BM$

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)

1

2

3

4

(3)

${}_{21}{Sc} = 3 d^{1} 4 s^{2}$ can show maximum +3 oxidation state but does not show +4 oxidation state.

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.

1

2

3

4

(3)

${CH}_{4}$ $(g)$ $+ H_{2} O$ $(g)$ $\to_{Ni}^{1270 K} CO$ $(g)$ $+ 3 H_{2}$ $(g)$

Hydrogenation of vegetable oils using Ni catalyst gives edible fats.

$C$ $(s)$ $+ H_{2} O$ $(g)$ $\overset{1270 K}{\to} CO$ $(g)$ $+ H_{2}$ $(g)$
(coal gasification)

Q 14 :

Highest oxidation state of Mn is exhibited in ${Mn}_{2} O_{7}$ . The correct statements about ${Mn}_{2} O_{7}$ 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

1

2

3

4

(2)

${Mn}_{2} O_{7}$

Q 15 :

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

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

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

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

1

2

3

4

(2)

In aqueous solution, ${Cu}^{+ 1}$ is unstable and it disproportionates.

$2 {Cu}^{+ 1} ⟶ Cu (s) + {Cu}^{+ 2} (a q)$

Hydration energy of ${Cu}^{2 +}$ is higher than ${Cu}^{+ 1}$ and this compensates its ionisation energy.

Q 16 :

Which of the following statements are correct?

(A) The $M^{3 +} / M^{2 +}$ 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 ${Cr}^{2 +}$ can liberate hydrogen from dilute acid.

(D) Magnetic moment of $V^{2 +}$ 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

1

2

3

4

(4)

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

$E_{{Mn}^{3 +} / {Mn}^{2 +}}^{\circ} = + 1.57 V$

$E_{{Fe}^{3 +} / {Fe}^{2 +}}^{\circ} = + 0.77 V$

(B) ${CrO}_{4}^{- 2}, {MnO}_{4}^{-}$

(C) ${Cr}^{2 +} (aq) + H^{+} (aq) \to {Cr}^{3 +} (aq) + \frac{1}{2} H_{2} ↑$

(D) $V^{2 +}$ has three unpaired electrons therefore magnetic moment is 3.87 BM.

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)

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

(2)

Q 18 :

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

(6)

The oxidation state of Mo in ammonium phosphomolybdate = +6

${({NH}_{4})}_{3} {PO}_{4} . 12 {MoO}_{3}$

Q 19 :

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

(4)

We have, $\sqrt{n (n + 2)} = 4.9 B.M$

$n (n + 2) = 24$

$n^{2} + 2 n - 24 = 0$

$n^{2} + 6 n - 4 n - 24 = 0$

$n (n + 6) - 4 (n + 6) = 0$

$∴$ $n = 4$

where $n =$ number of unpaired electrons.

Q 20 :

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

$A \overset{aqua-regia}{\to} B \to_{(2) AcOH}^{{(1) KNO}_{2} | {NH}_{4} OH} yellow ppt$ [2025]

ZnS
CoS
MnS
NiS

1

2

3

4

(2)

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]

${Ti}^{3 +}$
${Ni}^{2 +}$
${Mn}^{2 +}$
${Cr}^{3 +}$

1

2

3

4

(2)

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

1

2

3

4

(2)

Q 23 :

Identify the inorganic sulphides that are yellow in colour :

(A) ${({NH}_{4})}_{2} S$
(B) PbS
(C) CuS
(D) ${As}_{2} S_{3}$
(E) ${As}_{2} S_{5}$

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

1

2

3

4

(4)

Q 24 :

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

(15)

Q 25 :

The nature of oxide ( ${TeO}_{2}$ ) and hydride ( ${TeH}_{2}$ ) formed by Te, respectively are: [2025]

Oxidising and acidic
Reducing and basic
Reducing and acidic
Oxidising and basic

1

2

3

4

(1)

Q 26 :

A molecule with the formula ${AX}_{2} Y_{2}$ 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

1

2

3

4

(1)

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 ${Al}^{3 +}$ is less than that of ${Ga}^{3 +}$ .

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

1

2

3

4

(3)

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

1

2

3

4

(4)

$Lightest element of Group 7 \Rightarrow Mn$

$K_{2} {MnO}_{4} \Rightarrow Green$

Q 29 :

The oxidation state of chromium in the final product formed in the reaction between $KI$ and acidified $K_{2} {Cr}_{2} O_{7}$ solution is: [2026]

+4
+2
+6
+3

1

2

3

4

(4)

$K_{2} {Cr}_{2} O_{7} + KI \overset{H^{+}}{\to} I_{2} + {Cr}^{3 +}$

Q 30 :

Which of the following statement is incorrect?

$T l^{+ 3}$ is an oxidizing agent
${In}^{+ 1}$ is reducing agent
$T l$ form $M_{2} O$ type oxide
${Pb}^{+ 4}$ is a reducing agent

1

2

3

4

(4)

Inert pair effect

Q 31 :

Number of unpaired electrons in ${Mn}^{+ 7} = a$

Number of d-subshell electrons in Cr = b

Number of f-subshell electrons in Hf (Atomic no. = 72) = c

Find the value of $c - b + a$ .

(9)

$a = 0, b = 5, c = 14$

Q 32 :

If $λ_{0}$ and $λ$ be threshold wavelength and wavelength of incident light, the velocity of photoelectrons ejected from the metal surface is :

$\sqrt{\frac{2 h}{m} (λ_{0} - λ)}$
$\sqrt{\frac{2 h c}{m} (λ_{0} - λ)}$
$\sqrt{\frac{2 h c}{m} (\frac{λ_{0} - λ}{λ λ_{0}})}$
$\sqrt{\frac{2 h}{m} (\frac{1}{λ_{0}} - \frac{1}{λ})}$

1

2

3

4

(3)

$\frac{h c}{λ} = \frac{h c}{λ_{0}} + \frac{1}{2} m v^{2}$

$\frac{1}{2} m v^{2} = \frac{h c}{λ} - \frac{h c}{λ_{0}}$

$m v^{2} = 2 c h [\frac{1}{λ} - \frac{1}{λ_{0}}]$

$v^{2} = \frac{2 h c}{m} [\frac{λ_{0} - λ}{λ λ_{0}}]$

$v = \sqrt{\frac{2 h c}{m} [\frac{λ_{0} - λ}{λ λ_{0}}]}$

Q 33 :

The correct order of first ( $Δ_{i} H_{1}$ ) and second ( $Δ_{i} H_{2}$ ) ionisation enthalpy values of Cr and Mn are:

A. $Δ_{i} H_{1} : Cr > Mn$

B. $Δ_{i} H_{2} : Cr > Mn$

C. $Δ_{i} H_{1} : Mn > Cr$

D. $Δ_{i} H_{2} : Mn > Cr$

Choose the correct answer from the options given below: [2026]

A and B only
B and C only
A and D only
C and D only

1

2

3

4

(2)

Removal of one electron from Cr gives a stable half filled electronic configuration. Hence first ionization energy of Cr is less than that of Mn.

${}_{25}{Cr} ({}_{18}{[Ar]} 3 d^{5} 4 s^{1}) \overset{{IE}_{1}}{\to} {Cr}^{+}$ $({}_{18}{[Ar]} 3 d^{5})$ $\overset{{IE}_{2}}{\to} {Cr}^{2 +}$ $({}_{18}{[Ar]} 3 d^{4})$

To remove second electron of Cr, stable half filled electronic configuration of $({Cr}^{+})$ is disturbed. Hence second ionization energy of Cr is more than that of Mn.

${}_{25}{Mn} ({}_{18}{[Ar]} 3 d^{5} 4 s^{2}) \overset{{IE}_{1}}{\to} {Mn}^{+}$ $({}_{18}{[Ar]} 3 d^{5} 4 s^{1})$ $\overset{{IE}_{2}}{\to} {Mn}^{2 +}$ $({}_{18}{[Ar]} 3 d^{5})$

Q 34 :

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

Statement I: First row transition metals which act as catalyst utilise their $3 d$ electrons only for formation of bonds between reaction 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: [2026]

Both Statement I and Statement II are correct
Both Statement I and Statement II are incorrect
Statement I is correct but Statement II is incorrect
Statement I is incorrect but Statement II is correct

1

2

3

4

(2)

Statement I: Both $3 d$ and $4 s$ orbitals are used by first row transition metals for formation of bonds between reactant molecules and atoms on the surface of catalyst.

Statement II: Increases of concentration of reactant molecules weakens the bonds in reacting molecules.

Q 35 :

Given below are two statements:

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

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

In the light of the above statements, choose the correct answer from the options given below: [2026]

Both Statement I and Statement II are correct
Both Statement I and Statement II are incorrect
Statement I is correct but Statement II is incorrect
Statement I is incorrect but Statement II is correct

1

2

3

4

(1)

Statement I:

Ions	Electronic configuration	Number of unpaired electrons
${Ti}^{4 +}$	${}_{18}{[Ar]}$ $3 d^{0} 4 s^{0}$	0
$V^{2 +}$	${}_{18}{[Ar]}$ $3 d^{3} 4 s^{0}$	3
${Mn}^{2 +}$	${}_{18}{[Ar]}$ $3 d^{5} 4 s^{0}$	5
${Fe}^{3 +}$	${}_{18}{[Ar]}$ $3 d^{5} 4 s^{0}$	5
${Cr}^{2 +}$	${}_{18}{[Ar]}$ $3 d^{4} 4 s^{0}$	4

As ${Ti}^{4 +}$ has no unpaired electron, it is colourless. Rest ions are coloured.

Statement II:

Ions	Electronic configuration	Number of unpaired electrons
${La}^{3 +}$	${}_{54}{[Xe]}$ $5 d^{0} 6 s^{0}$	0
${Yb}^{2 +}$	${}_{54}{[Xe]}$ $4 f^{14}$	0
${Lu}^{3 +}$	${}_{54}{[Xe]}$ $4 f^{14}$	0
${Ce}^{4 +}$	${}_{54}{[Xe]}$ $4 f^{0}$	0
${Ac}^{3 +}$	${}_{86}{[Rn]}$ $5 f^{0}$	0
${Lr}^{3 +}$	${}_{86}{[Rn]}$ $5 f^{14}$	0

As all ions have paired electrons, all are diamagnetic.

Q 36 :

Among ${Fe}^{3 +}$ , ${Pb}^{2 +}$ , ${Cu}^{2 +}$ and ${Mn}^{2 +}$ , identify the one that gets precipitated out while passing $H_{2} S$ in presence of ${NH}_{4} OH$ as group reagent. The highest possible oxidation state of the corresponding metal is [2026]

+3
+4
+2
+7

1

2

3

4

(4)

$H_{2} S + {NH}_{4} OH$ is group 4 reagent. ${Mn}^{2 +}$ is group 4 cation and gets precipitated as $MnS$ . Highest oxidation state of $Mn$ is +7. Note: question needs modification. Cations belonging to group 1, 2 and 3 are also precipitated as sulphides by group 4 reagent. ${Fe}^{3 +}$ -group 3, ${Pb}^{2 +}$ and ${Cu}^{2 +}$ -group 2.

Q 37 :

Among ${Fe}^{2 +}$ , ${Fe}^{3 +}$ , ${Cr}^{2 +}$ and ${Zn}^{2 +}$ , the ion that shows positive borax bead test and with highest ionisation enthalpy is: [2026]

${Fe}^{2 +}$
${Zn}^{2 +}$
${Cr}^{2 +}$
${Fe}^{3 +}$

1

2

3

4

(4)

Borax bead test is mainly for elements that show variable oxidation states, such as Cu, Fe, Cr, Mn, Co, and Ni. ${Zn}^{2 +}$ , hence does not show Borax bead test as Zn does not show variable oxidation state. Among remaining ions ${Fe}^{3 +}$ has maximum ionization enthalpy.

Topic Question Set

Q 11 :

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

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.

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)

$V^{3 +}$ , ${Cr}^{3 +}$ , ${Fe}^{2 +}$ , ${Ni}^{3 +}$ [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.

$A \overset{aqua-regia}{\to} B \to_{(2) AcOH}^{{(1) KNO}_{2} | {NH}_{4} OH} yellow ppt$ [2025]

(2)

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]

(2)

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)

Q 23 :

Identify the inorganic sulphides that are yellow in colour :

(A) ${({NH}_{4})}_{2} S$
(B) PbS
(C) CuS
(D) ${As}_{2} S_{3}$
(E) ${As}_{2} S_{5}$

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

(4)

Q 24 :

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

Q 25 :

The nature of oxide ( ${TeO}_{2}$ ) and hydride ( ${TeH}_{2}$ ) formed by Te, respectively are: [2025]

(1)

(1)

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 ${Al}^{3 +}$ is less than that of ${Ga}^{3 +}$ .

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

(3)

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]

Q 29 :

The oxidation state of chromium in the final product formed in the reaction between $KI$ and acidified $K_{2} {Cr}_{2} O_{7}$ solution is: [2026]

Q 30 :

Which of the following statement is incorrect?

Q 31 :

Number of unpaired electrons in ${Mn}^{+ 7} = a$

Number of d-subshell electrons in Cr = b

Number of f-subshell electrons in Hf (Atomic no. = 72) = c

Find the value of $c - b + a$ .

Q 32 :

If $λ_{0}$ and $λ$ be threshold wavelength and wavelength of incident light, the velocity of photoelectrons ejected from the metal surface is :

Q 36 :

Among ${Fe}^{3 +}$ , ${Pb}^{2 +}$ , ${Cu}^{2 +}$ and ${Mn}^{2 +}$ , identify the one that gets precipitated out while passing $H_{2} S$ in presence of ${NH}_{4} OH$ as group reagent. The highest possible oxidation state of the corresponding metal is [2026]

Q 37 :

Among ${Fe}^{2 +}$ , ${Fe}^{3 +}$ , ${Cr}^{2 +}$ and ${Zn}^{2 +}$ , the ion that shows positive borax bead test and with highest ionisation enthalpy is: [2026]

Want Us to Email you About Special Offers & Updates?

Topic Question Set

Q 11 : The magnetic moment of transition metal compound has been calculated to be 3.87 B.M. The metal ion is [2023]

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.

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) V3+, Cr3+, Fe2+, Ni3+ [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→aqua-regiaB→(2) AcOH(1) KNO2| NH4OHyellow ppt [2025]

(2)

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]

(2)

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)

Q 23 : Identify the inorganic sulphides that are yellow in colour : (A) (NH4)2S (B) PbS (C) CuS (D) As2S3 (E) As2S5 Choose the correct answer from the options given below : [2025]

(4)

Q 24 : A group 15 element forms dπ–dπ bond with transition metals. It also forms hydride, which is a strongest base among the hydrides of other group members that form dπ–dπ bond. The atomic number of the element is ____. [2025]

Q 25 : The nature of oxide (TeO2) and hydride (TeH2) formed by Te, respectively are: [2025]

(1)

(1)

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 Al3+ is less than that of Ga3+. In the light of the above statements, choose the most appropriate answer from the options given below:

(3)

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]

Q 29 : The oxidation state of chromium in the final product formed in the reaction between KI and acidified K2Cr2O7 solution is: [2026]

Q 30 : Which of the following statement is incorrect?

Q 31 : Number of unpaired electrons in Mn+7=a Number of d-subshell electrons in Cr = b Number of f-subshell electrons in Hf (Atomic no. = 72) = c Find the value of c−b+a.

Q 32 : If λ0 and λ be threshold wavelength and wavelength of incident light, the velocity of photoelectrons ejected from the metal surface is :

Q 33 : The correct order of first (ΔiH1) and second (ΔiH2) ionisation enthalpy values of Cr and Mn are: A. ΔiH1:Cr>Mn B. ΔiH2:Cr>Mn C. ΔiH1:Mn>Cr D. ΔiH2:Mn>Cr Choose the correct answer from the options given below: [2026]

Q 36 : Among Fe3+, Pb2+, Cu2+ and Mn2+, identify the one that gets precipitated out while passing H2S in presence of NH4OH as group reagent. The highest possible oxidation state of the corresponding metal is [2026]

Q 37 : Among Fe2+, Fe3+, Cr2+ and Zn2+, the ion that shows positive borax bead test and with highest ionisation enthalpy is: [2026]

Want Us to Email you About Special Offers & Updates?

Q 11 :

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

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.

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)

$V^{3 +}$ , ${Cr}^{3 +}$ , ${Fe}^{2 +}$ , ${Ni}^{3 +}$ [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.

$A \overset{aqua-regia}{\to} B \to_{(2) AcOH}^{{(1) KNO}_{2} | {NH}_{4} OH} yellow ppt$ [2025]

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]

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]

Q 23 :

Identify the inorganic sulphides that are yellow in colour :

(A) ${({NH}_{4})}_{2} S$
(B) PbS
(C) CuS
(D) ${As}_{2} S_{3}$
(E) ${As}_{2} S_{5}$

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

Q 24 :

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

Q 25 :

The nature of oxide ( ${TeO}_{2}$ ) and hydride ( ${TeH}_{2}$ ) formed by Te, respectively are: [2025]

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 ${Al}^{3 +}$ is less than that of ${Ga}^{3 +}$ .

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

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]

Q 29 :

The oxidation state of chromium in the final product formed in the reaction between $KI$ and acidified $K_{2} {Cr}_{2} O_{7}$ solution is: [2026]

Q 30 :

Which of the following statement is incorrect?

Q 31 :

Number of unpaired electrons in ${Mn}^{+ 7} = a$

Number of d-subshell electrons in Cr = b

Number of f-subshell electrons in Hf (Atomic no. = 72) = c

Find the value of $c - b + a$ .

Q 32 :

If $λ_{0}$ and $λ$ be threshold wavelength and wavelength of incident light, the velocity of photoelectrons ejected from the metal surface is :

Q 36 :

Among ${Fe}^{3 +}$ , ${Pb}^{2 +}$ , ${Cu}^{2 +}$ and ${Mn}^{2 +}$ , identify the one that gets precipitated out while passing $H_{2} S$ in presence of ${NH}_{4} OH$ as group reagent. The highest possible oxidation state of the corresponding metal is [2026]

Q 37 :

Among ${Fe}^{2 +}$ , ${Fe}^{3 +}$ , ${Cr}^{2 +}$ and ${Zn}^{2 +}$ , the ion that shows positive borax bead test and with highest ionisation enthalpy is: [2026]