CBSE Class 12 Chemistry Transition Elements Worksheet

Question. The transitional metal which forms green compound in +3 oxidation state and yellow orange compound in +6 oxidation state is?
a. Fe
b. Ni
c. Cr
d. Co
Answer : C

Question. In a reaction the ferrous (Fe⁺⁺) iron is oxidised to ferric (Fe++) ion. The equivalent weight of the ion in the above reaction is equal to:
a. Half of the atomic weight
b. 1/5 of the atomic weight
c. The atomic weight
d. Twice the atomic weight
Answer : C

Question. Which is most reactive metal?
a. Fe
b. Pt
c. Ni
d. Co
Answer : A

Question. The decrease in atomic volume from Cr to Cu is very negligible because:
a. Increase in nuclear change
b. Screening effect
c. Unpaired electrons of Cr
d. None
Answer : B

Question. The number of oxidation states of manganese is:
a. 4
b. 6
c. 3
d. 8
Answer : B

Question. The tendency towards complex formation is maximum in:
a. s - block elements
b. p - block elements
c. d - block elements
d. f - block elements
Answer : C

Question. Which is not true for transition elements?
a. They are all metals
b. They show variable valency
c. They form coloured ions
d. They do not form co-ordinate compounds
Answer : D

Question. Which element gives maximum balanced oxide?
a. V
b. Cr
c. Mn
d. Fe
Answer : C

Question. In which of the following metallic bond is strongest?
a. Fe
b. Sc
c. V
d. Cr
Answer : D

Question. Which of the following elements is alloyed with copper to form brass?
a. Lead
b. Silver
c. Zinc
d. Antimony
Answer : C

Question. How many unpaired electrons are there in 2 Ni + ?
a. 2
b. 4
c. 5
d. 0
Answer : A

Question. Which of the following have maximum number of unpaired electrons?
a. Fe³⁺
b. Fe²⁺
c. Co²⁺
d. Co³⁺
Answer : A

Question. Which of the following element has maximum first ionisation potential?
a. V
b. Ti
c. Cr
d. Mn
Answer : D

Question. Electronic configuration of Cu(Z=29) is:
a. [Ar]3d⁹ 4s²
b. [Ar]3d¹⁰ 4s²
c. [Ar]3d² 4s²
d. [Ar]3d⁶ 4s²
Answer : B

Question. The magnetic moment of a metal ion of first transition series is 2.83BM. Therefore it will have unpaired electrons:
a. 6
b. 4
c. 3
d. 2
Answer : D

Question. The valence shell electronic configuration of Cr²⁺ ion is:
a. o 4 4s 3d
b. 2 2 4s 3d
c. 2 0 4s 3d
d. 6 2 3p 4s
Answer : A

Question. Transition metals are related to which block?
a. s-block
b. p-block
c. d-block
d. None of these
Answer : B

Question. The oxidation number of iron in potassium ferrocyanide i
a. +2
b. +3
c. +4
d. Zero
Answer : A

Question. The atomic radii of the elements are almost same of which series?
a. Fe − Co − Ni
b. Na − K − Rb
c. F − Cl − Br
d. Li − Be − B
Answer : A

Question. Which of the following structure is that of a coinage metal?
a. 2, 8, 1
b. 2, 8, 18, 1
c. 2, 8, 8
d. 2, 18, 8, 3
Answer : B

Question. Which of the following transition metal cation has maximum unpaired electrons?
a. Mn⁺²
b. Fe⁺²
c. Co²⁺
d. Ni²⁺
Answer : A

Question. Which of the following statements is not true in regard to transition elements?
a. They readily form complex compounds
b. They show variable valency
c. All their ions are colourless
d. Their ions contain partially filled d -electron levels
Answer : C

Question. Which belongs to the actinides series?
a. Ce
b. Cf
c. Ca
d. Cs
Answer : B

Question. Effective magnetic droment of Sc+3 ion is:
a. 1.73
b. 0
c. 5.92
d. 2.83
Answer : B

Question. On the basis of position in the electrochemical series, the metal which does not displace hydrogen from water and acid is?
a. Hg
b. Al
c. Pb
d. Ba
Answer : A

Question. Which of the following represents the electronic configuration of a transition element?
a. 1s² ,2s² p⁶ .......ns² p³
b. 1s² ,2s² p⁶ .......ns² p⁶ d³ , (n +1)s²
c. 1s² ,2s² p⁶ .......ns² p⁶ d¹⁰ , (n +1)s² p¹
d. 1s² , 2s² p⁶ .......ns² p⁶
Answer : B

Question. Which of the following is not an actinide?
a. Curium
b. Californium
c. Uranium
d. Terbium
Answer : D

Question. Which of the following is not true for transition metals?
a. They are malleable and ductile
b. They have high boiling and melting points
c. They crystallize with body centred cubic and hexagonal close-packed structures only
d. They show variable oxidation states although not always
Answer : C

Question. Which of the following ions is paramagnetic?
a. Cu⁺
b. Zn⁺²
c. Ti⁺³
d. Ti⁺⁴
Answer : C

Question. Iron is rendered passive by the action of:
a. Conc. H₂SO₄
b. Conc. H₃PO₄
c. Conc. HCl
d. Conc. HNO₃
Answer : D

Question. From +6 to +1 oxidation state is shown by the element of....... group:
a. V-B
b. VI-B
c. VII-B
d. VIII
Answer : B

Question. Fe²⁺ shows:
a. Ferromagnetism
b. Paramagnetism
c. Diamagnetism
d. None of these
Answer : B

Question. Rare-earth elements are exhibited by:
a. At. No. 58 to 71
b. At. No. 21 to 30
c. At. No. 39 to 71
d. At. No. 81 to 91
Answer : A

Question. The tendency of 3d-metal ions to form stable complexes is due to their:
a. Variable oxidation state
b. Strong electronegative nature
c. High charge/size ratio and vacant d-orbitals
d. Very low ionization energies
Answer : C

Question. Fe, Co and Ni have valuable catalytic properties in process involving:
a. Organic compound
b. Oxidation
c. Hydrogenation
d. Compounds of hydrogen f-Block Elements
Answer : C

Question. Which of the following oxides of manganese is amphoteric?
(a) MnO₂
(b) Mn₂O₃
(c) Mn₂O7
(d) MnO
Answer : A

Question. In which of the following compounds manganese has oxidation number equal to that of iodine in KIO₄ ?
(a) Potassium manganate
(b) Potassium permanganate
(c) Manganous chloride
(d) Manganese chloride
Answer : B

Question. Which of the following statement is not true about Mohr's salt?
a. It decolourises KMnO₄
b. It is a primary standard
c. It is a double salt
d. Oxidation state of iron is +3 in this salt
Answer : D

Question. Which of the following transition metal is present in misch metal?
a. La
b. Sc
c. Ni
d. Cr
Answer : A

Question. The hardness of Cr is due to ...... and metallic lusture is due to .......
a. Covalent bond, metallic bond
b. Covalent bond, hydrogen bond
c. Metallic bond, covalent bond
d. Metallic bond, hydrogen bond
Answer : A

Question. In the first transition series, the highest B.P. and M.P. is of:
a. Cr
b. V
c. Ni
d. Fe
Answer : A

Question. In the following transition elements, the lowest M.P. and B.P. is exhibited by:
a. Cr
b. Hg
c. Cu
d. Au
Answer : B

Question. Which of the following element does not show variable valency?
a. Ni
b. Zn
c. Cu
d. Mn
Answer : B

Question. Which of the following is diamagnetic transitional metal ion?
a. Ni⁺²
b. Zn⁺²
c. Co⁺²
d. Cu⁺²
Answer : B

Question. The correct order of ionic radii of Y³⁺, La³⁺, Eu³⁺ and Lu³⁺ is
(a) La³⁺ < Eu³⁺ < Lu³⁺ < Y³⁺
(b) Y³⁺ < La³⁺ < Eu³⁺ <Lu³⁺
(c) Y³⁺ < Lu³⁺ < Eu³⁺ < La³⁺
(d) Lu³⁺ < Eu³⁺ < La³⁺ < Y³⁺
(Atomic nos. Y =39, La = 57, Eu = 63, Lu = 71)
Answer : C

Question. Railway wagon axles are made by heating rods of iron embedded in charcoal powder. The process is known as:
a. Case hardening
b. Sheradizing
c. Annealing
d. Tempering
Answer : A

Question. What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid?
(a) Cr₂O₇^2- and H₂O are formed
(b) CrO₄^2- is reduced to +3 state of Cr
(c) CrO₄^2- is oxidized to +7 state of Cr
(d) Cr³⁺ and Cr₂O₇^2- are formed
Answer : A

Question. Which has the maximum ferromagnetic character?
a. Fe
b. Co
c. Ni
d. Pt
Answer : A

Question. Which forms interstitial compounds?
a. Fe
b. Co
c. Ni
d. All of these
Answer : D

Question. Which occurs in nature in free-state?
a. Fe
b. Co
c. Ni
d. Pt
Answer : D

Question. Which of the following ions has the least magnetic moment?
a. Cu⁺²
b. Ni⁺²
c. Co⁺³
d. Fe⁺²
Answer : A

Question. Among the following outermost configurations of transition metals, which shows the highest oxidation state?
a. 3d³ 4s²
b. 3d⁵ 4s²
c. 3d⁵ 4s²
d. 3d⁶ 4s²
Answer : C

Question. For the four successive transition elements (Cr, Mn, Fe and Co), the stability of +2 oxidation state will be there in which of the following order?
(a) Mn > Fe > Cr > Co
(b) Fe > Mn > Co > Cr
(c) Co > Mn > Fe > Cr
(d) Cr > Mn > Co > Fe
Answer : A

Question. Which of the following compound is called Turnbull’s blue?
(a) Ferricyanide
(b) Ferrous ferricyanide
(c) Ferrous cyanide
(d) Ferri-ferrocyanide
Answer : B

Question. A compound of a metal ion Mx+ (Z = 24) has a spin only magnetic moment of 15 Bohr Magnetons. The number of unpaired electrons in the compound are
(a) 2
(b) 4
(c) 5
(d) 3
Answer : D

Question. Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them?
a. (n −1)d³ ns²
b. (n −1)d⁵ ns²
c. (n −1)d⁸ ns²
d. (n −1)d⁵ ns²
Answer : D

Question. Among the following series of transition metal ions, the one where all metals ions have 3d² electronic configuration is?
a. Ti⁴⁺ , V³⁺, Cr²⁺, Mn³⁺ 
b. Ti²⁺ , V³⁺, Cr⁴⁺, Mn⁵⁺
c. Ti³⁺, V²⁺, Cr³⁺ , Mn⁴⁺
d. Ti⁺ ,  V⁴⁺,  Cr⁶⁺, Mn⁷⁺ 
Answer : B

Question. In photography sodium thiosulphate is used as:
a. Complexing agent
b. Oxidising agent
c. Reducing agent
d. None of these
Answer : A

Question. The form of iron having the highest carbon content is:
a. Cast iron
b. Wrought iron
c. Strain steel
d. Mild steel
Answer : A

Question. The roasting of HgS in air produces
(a) HgO
(b) HgSO₃
(c) HgSO₄
(d) Hg
Answer : D

Question. When MnO₂ is fused with KOH, a coloured compound is formed, the product and its colour is:
(a) K₂MnO₄, purple green
(b) KMnO₄, purple
(c) Mn₂O₃, brown
(d) Mn₃O₄, black
Answer : A

Question. If an aqueous solution of KCN is added to a solution of ferrous salt then the complex formed is represented by
(a) [Fe(CN)₆]^4-
(b) [Fe(CN)₆]^3-
(c) [Fe(H₂O)₆]³⁺
(d) [Fe(H₂O)₆]²⁺
Answer : A

Question. In solid CuSO₄ .5H₂O copper is co-ordinated to:
a. Five water molecules
b. Four water molecules
c. One sulphate anion
d. One water molecule
Answer : B

Question. In which of the following ionic radii of chromium would be smallest?
a. 2 4 K CrO
b. 2 CrO
c. 3 CrCl
d. 2 CrF
Answer : A

Question. Which of the following metals absorbs hydrogen?
a. K
b. Al
c. Zn
d. Pd
Answer : D

Question. Which of the following ions is coloured?
a. Cu⁺
b. Cu²⁺
c. Ti⁴⁺
d. V⁵⁺
Answer : B

Question. The equivalent weight of potassium permanganate for acid solution is:
a. 158
b. 31.6
c. 52.16
d. 79
Answer : B

Question. Which is an amphoteric oxide?
a. ZnO
b. CaO
c. BaO
d. SrO
Answer : A

Question. Percentage of silver in German silver is:
a. 0%
b. 1%
c. 5%
d. None of these
Answer : D

Question. Which of the following sulphides is yellow in colour?
a. CuS
b. CdS
c. ZnS
d. CoS
Answer : B

Question. Mercury (I) chloride sublimes, when this compound is heated and the vapours it gives off are cooled the substance collected consists of
(a) Mercury (II) chloride
(b) Mercury (I) and Mercury (II), chlorides
(c) Mercury (II) chloride and mercury
(d) Mercury
Answer : D

Question. In neutral or faintly alkaline medium, thiosulphate is quantitatively oxidized by KMnO₄ to
(a) SO₃^2–
(b) SO₄^2–
(c) SO₂
(d) SO₅^2–
Answer : B

Question. An excess of Na₂S₂O₃ reacts with aqueous CuSO₄ to give
(a) CuS₂O₃
(b) Cu₂S₂O₃
(c) Na₂[Cu(S₂O₃)₂]
(d) Na₄[Cu₆(S₂O₃)₅]
Answer : D

Question. Which of the following oxides of Cr is amphoteric
(a) CrO₂
(b) Cr₂O₃
(c) CrO₅
(d) CrO₃
Answer : A

Question. Consider the following statements
(I) La(OH)₃ is the least basic among hydroxides of lanthanoids.
(II) Zr⁴⁺ and Hf⁴⁺ posses almost the same ionic radii.
(III) Ce⁴⁺ can as an oxidizing agent.
Which of the above is/are true ?
(a) (I) and (III)
(b) (II) and (III)
(c) (II) only
(d) (I) and (II)
Answer : B

Numeric Value Answer

Question. The number of water molecule(s) directly bonded to the metal centre in CuSO₄.5H₂O is
Answer : 4

Question. Out of the following, how many oxides are acidic.
MnO, Mn₂O₃, MnO₂, MnO₃, Mn₂O₇
Answer : 3

Question. What is the oxidation states of Cr in butterfly structure.
Answer : 6

Question. The oxidation number of Mn in the product of alkaline oxidative fusion of MnO₂ is
Answer : 6

Question. A light blue coloured compound (A) on heating gives a block compound (B) which reacts with glucose to give a red compound (C). After the completion of reaction, how many metal oxides are formed?
Answer : 2

Q1. Give reasons for the following:-

(a) As compared to elements of the first transition series, heavier transition metals of second & third transition series show more frequent metal - metal bonding.

(b) Elements of second and third d series have similar radii.

(c) The unipositive transition metal ion have d" configuration.

(d) Scandium (II) is virtually unknown.

(e) Titanium (IV) is more stable than Titanium (II) or Titanium (III).

(f) Oxidation states in transition elements vary from each other by unity (eg V(ll) V(IlI) V(JV) V(V) whereas oxidation states of non transition states normally differ by a unit of two.

(g) In non transition elements; lower transition state is favoured by heavier elements whereas in transition elements higher transition state is favoured by heavier elements.  

TRANSITION ELEMENTS

Q1. Give reasons for the following:-

(a) As compared to elements of the first transition series, heavier transition metals of second & third transition series show more frequent metal – metal bonding.

(b) Elements of second and third d series have similar radii.

(c) The unipositive transition metal ion have dn configuration.

(d) Scandium (II) is virtually unknown.

(e)Titanium (IV) is more stable than Titanium (II) or Titanium (III).

(f) Oxidation states in transition elements vary from each other by unity (eg V(II) V(III) V(IV) V(V) whereas oxidation states of non transition states normally differ by a unit of two.

(g) In non transition elements; lower transition state is favoured by heavier elements whereas in transition elements higher transition state is favoured by heavier elements.

(h) E⁰M⁺² /M value for Mn, Ni & Zn is more negative expected.

(i) Highest Mn fluoride is MnF4 with Mn in +4 O.S. whereas highest Mn oxide is Mn₂O₇ with Mn in +7 O.S.

(j) For Cu Δ _iH0₁ = 745 KJ/mol whereas Δ _iH0₂ = 1940 KJ/mol, Inspite of very high second ionization enthalpy more stable O.S. of Cu in aqueous medium is +2

(k) V₂O₃ is basic while V₂O₅ is amphoteric

(l) Lanthanides resemble each other more closely than do members of ordinary transition series

(m) La & Lu do not show any colour

(n) Actinides show greater range of O.S. as compared to lanthanides.

(o) Ionization enthalpy of early actinides is lower than that of early lanthanides.

(p) Study of actinides is comparatively difficult.