CBSE Class 12 Chemistry D And F Block Elements Question Bank Set B

Read and download free pdf of CBSE Class 12 Chemistry D And F Block Elements Question Bank Set B. Download printable Chemistry Class 12 Worksheets in pdf format, CBSE Class 12 Chemistry Unit 8 The d- and f-Block Elements Worksheet has been prepared as per the latest syllabus and exam pattern issued by CBSE, NCERT and KVS. Also download free pdf Chemistry Class 12 Assignments and practice them daily to get better marks in tests and exams for Class 12. Free chapter wise worksheets with answers have been designed by Class 12 teachers as per latest examination pattern

Unit 8 The d- and f-Block Elements Chemistry Worksheet for Class 12

Class 12 Chemistry students should refer to the following printable worksheet in Pdf in Class 12. This test paper with questions and solutions for Class 12 Chemistry will be very useful for tests and exams and help you to score better marks

Class 12 Chemistry Unit 8 The d- and f-Block Elements Worksheet Pdf

Question. K2Cr2O7 on heating with aqueous NaOH gives
(a) Cr2O72–
(b) Cr(OH)2
(c) CrO42–
(d) Cr(OH)3 
Answer. C

Question. KMnO4 reacts with oxalic acid according to the equation
2MnO4 + 5C2O42– + 16H+→ 2Mn2+ + 10CO2 + 8H2O
Here 20 mL of 0.1 M KMnO4 is equivalent to
(a) 50 mL of 0.5 M C2H2O4
(b) 20 mL of 0.1 M C2H2O4
(c) 20 mL of 0.5 M C2H2O4
(d) 50 mL of 0.1 M C2H2O4
Answer. D

Question. The oxidation state of Cr in K2Cr2O7 is
(a) +5
(b) +3
(c) +6
(d) +7 
Answer. C

Question. Which one of the following statements related to lanthanons is incorrect?
(a) Europium shows +2 oxidation state.
(b) The basicity decreases as the ionic radius decreases from Pr to Lu.
(c) All the lanthanons are much more reactive than aluminium.
(d) Ce(+4) solutions are widely used as oxidizing agent in volumetric analysis. 
Answer. C

Question. The electronic configurations of Eu (Atomic No. 63), Gd (Atomic No. 64) and Tb (Atomic No. 65) are
(a) [Xe]4f 65d16s2, [Xe]4f 75d16s2 and [Xe]4f 85d16s2
(b) [Xe]4f 7 6s2, [Xe]4f 7 5d1 6s2 and [Xe]4f 9 6s2
(c) [Xe]4f 7 6s2, [Xe]4f 8 6s2 and [Xe]4f 8 5d1 6s2
(d) [Xe]4f 6 5d1 6s2, [Xe]4f 7 5d1 6s2 and [Xe]4f 9 6s2
Answer. B

Question. Gadolinium belongs to 4f series. Its atomic number is 64. Which of the following is the correct electronic configuration of gadolinium?
(a) [Xe] 4f 9 5s1
(b) [Xe] 4f 75d16s2
(c) [Xe] 4f 65d26s2
(d) [Xe] 4f 86d2
Answer. B

Question. Because of lanthanoid contraction, which of the following pairs of elements have nearly same atomic radii? (Numbers in the parenthesis are atomic numbers)
(a) Zr(40) and Hf(72)
(b) Zr(40) and Ta(73)
(c) Ti(22) and Zr(40)
(d) Zr(40) and Nb(41)
Answer. A

Question. Reason of lanthanoid contraction is
(a) negligible screening effect of ‘f ’-orbitals
(b) increasing nuclear charge
(c) decreasing nuclear charge
(d) decreasing screening effect.
Answer. A

Question. Which of the following lanthanoid ions is diamagnetic?
(At. nos. Ce = 58, Sm = 62, Eu = 63, Yb = 70)
(a) Eu2+
(b) Yb2+
(c) Ce2+
(d) Sm2+
Answer. B

Question. Which of the following oxidation states is the most common among the lanthanoids?
(a) 4
(b) 2
(c) 5
(d) 3
Answer. D

Question. Identify the incorrect statement among the following :
(a) Lanthanoid contraction is the accumulation of successive shrinkages.
(b) As a result of lanthanoid contraction, the properties of 4d series of the transition elements have no similarities with the 5d series of elements.
(c) Shielding power of 4f electrons is quite weak.
(d) There is a decrease in the radii of the atoms or ions as one proceeds from La to Lu. 
Answer. B

Question. Lanthanoids are
(a) 14 elements in the sixth period (atomic no. 90 to 103) that are filling 4f sublevel
(b) 14 elements in the seventh period (atomic number = 90 to 103) that are filling 5f sublevel
(c) 14 elements in the sixth period (atomic number = 58 to 71) that are filling the 4f sublevel
(d) 14 elements in the seventh period (atomic number = 58 to 71) that are filling 4f sublevel.
Answer. C

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

Question. General electronic configuration of lanthanides is
(a) (n – 2) f1 – 14 (n – 1) s2p6d0 – 1 ns2
(b) (n – 2) f10 – 14 (n – 1) d0 – 1 ns2
(c) (n – 2) f 0 – 14 (n – 1) d10 ns2
(d) (n – 2) d0 – 1 (n – 1) f1 – 14 ns2 
Answer. A

Question. Which of the following statement is not correct?
(a) La(OH)3 is less basic than Lu(OH)3.
(b) In lanthanide series ionic radius of Ln+3 ion decreases.
(c) La is actually an element of transition series rather lanthanides.
(d) Atomic radius of Zn and Hf are same because of lanthanide contraction.
Answer. A

Question. The lanthanide contraction is responsible for the fact that
(a) Zr and Hf have about the same radius
(b) Zr and Zn have the same oxidation state
(c) Zr and Y have about the same radius
(d) Zr and Nb have similar oxidation state. 
Answer. A

Question. Which of the following statements concerning lanthanide elements is false?
(a) All lanthanides are highly dense metals.
(b) More characteristic oxidation state of lanthanide elements is +3.
(c) Lanthanides are separated from one another by ion exchange method.
(d) Ionic radii of trivalent lanthanides steadily increases with increase in the atomic number.
Answer. D

Question. The reason for greater range of oxidation states in actinoids is attributed to
(a) actinoid contraction
(b) 5f, 6d and 7s levels having comparable energies
(c) 4f and 5d levels being close in energies
(d) the radioactive nature of actinoids.
Answer. B

Question. Which of the following exhibits only +3 oxidation state?
(a) U
(b) Th
(c) Ac
(d) Pa 
Answer. C

Question. More number of oxidation states are exhibited by the actinoids than by the lanthanoids. The main reason for this is
(a) more active nature of the actinoids
(b) more energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals
(c) lesser energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals
(d) greater metallic character of the lanthanoids than that of the corresponding actinoids.
Answer. C

Question. Which one of the following elements shows maximum number of different oxidation states in its compounds?
(a) Gd
(b) La
(c) Eu
(d) Am 
Answer. D

Question. Match the catalyst with the process : Catalyst Process
(i) V2O5                     (p) The oxidation of ethyne to ethanal
(ii) TiCl4 +Al(CH3)3   (q) Polymerisation of alkynes
(iii) PdCl2                  (r) Oxidation of SO2 in the manufacture of H2SO4
(iv) Nickel                 (s) Polymerisation complexes of ethylene
Which of the following is the correct option?
(a) (i)-(r), (ii)-(s), (iii)-(p), (iv)-(q)
(b) (i)-(p), (ii)-(q), (iii)-(r), (iv)-(s)
(c) (i)-(p), (ii)-(r), (iii)-(q), (iv)-(s)
(d) (i)-(r), (ii)-(p), (iii)-(s), (iv)-(q)
Answer. A

Question. HgCl2 and I2 both when dissolved in water containing I ions, the pair of species formed is
(a) HgI2, I
(b) HgI42–, I3
(c) Hg2I2, I
(d) HgI2, I3
Answer. B

Question. Which of the following elements is responsible for oxidation of water to O2 in biological processes?
(a) Cu
(b) Mo
(c) Fe
(d) Mn 
Answer. C

Question. When calomel reacts with NH4OH, we get
(a) Hg2O
(b) HgO
(c) HgNH2Cl
(d) NH2–Hg–Hg–Cl
Answer. C

Question. Photographic films and plates have an essential ingredient of
(a) silver nitrate
(b) silver bromide
(c) sodium chloride
(d) oleic acid.
Answer. B

 
 
1. Zinc, cadmium and mercury are not considered as transition metals. Why? 
 
2. Write the general configuration of d- block elements. 
 
3. What is the ore of K2Cr2O7 and KMnO4
 
4. What is the effect of adding a base to potassium dichromate? 
 
5. The chemistry of actionoids is more complicated than lanthanoids. Why? 
 
6. What is the general valence configuration of f-block elements? 
 
7. Actionoid contraction is more than lanthanoid contraction. Give reason. 
 
8. Actionoids show larger number of oxidation states than lanthanoids. Why? 
 
9. Write the electronic configuration of Cr3+ ion (atomic number of Cr = 24)? 
 
10. Explain CuSO4. 5H2O is blue while ZnSO4 and CuSO4 are colourless? 
 
11. Why is the third ionisation energy of Manganese (Z = 25) is unexpectedly high?
 
12. Silver (Ag) has completely filled d-orbitals (4d10) in its ground state. How can you say that it is a transition element.
 
13. The +3 oxidation state of lanthanum (Z = 57), gadolinium (Z = 64) and lutetium (Z = 71) are especially stable. Why?
 
14. Mention one consequence of Lanthanoid Contraction?
 
15. The first ionization enthalpies of 5d– series elements is higher than those of 3d and 4d series elements why?
 
16. Why Mn2+ compounds are more stable than Fe2+ compounds towards oxidation to their +3 state?
 
17. What are interstitial compounds? 
 
18. Write the chemical equation for the reaction of thiosulphate ions andalkaline potassium permanganate.
 
19. Write the electronic configuration of Lu3+ (At. No. = 71) 
 
20. What is the most common oxidation state of actinoids? 
 
21. Why is Cd2+ ion white? 
 
22. Transition metals generally form coloured ions. Why? 
 
23. Which of the following will be colored?
 
Sc3+, V2+, Mn2+, Cu+, Ni2+.
 
24. Give an explanation for the catalytic properties shown by transition metals. 
 
25. Draw the structure of chromate and dichromate ions? 
 
26. Describe the steps of preparation of KMnO4? 
 
27. Draw the structure of manganate and permanganate ions? 
 
28. What is the composition of misch metal? Give its one use. 
 
29. What happens when
(a) A lanthonoid reacts with dil- acid
(b) A lanthonoid reacts with water.
 
30. Write the chemical equation, when the yellow colour of aqueous solution of Na2CrO4 changes to orange on passing CO2 gas?
 
31. The stability of Cu2+ (aq) is more than that of Cu+ (aq). Why? 
 
32. Write complete chemical equations for
(a) Oxidation of Fe2+ by Cr2O7 in acidic medium
(b) Oxidation of Mn2+ by MnO4 in neutral or faintly alkaline medium.
 
33. (a) Why do transition metals show high melting points?
(b) Out of Fe and Cu, which one would exhibit higher melting point?
 
34. Describe giving reason which one of the following pairs has the propertyindicated :
(a) Cr2+ or Fe2+ (stronger reducing agent).
(b) Co2+ or Ni2+ (lower magnetic moments).
 
35. Of the ions Co2+, Sc3+, Cr3+ which one will give colourless aqueous solution and how will each of them respond to magnetic field and why?
 
36. Account for the following :
(a) Copper shows its inability to liberate hydrogen gas from the diluteacids.
(b) Scandium (Z = 21) does not exhibit variable oxidation states.
 
37. The following two reactions of HNO3 with Zn are given.
(a) Zn + conc. HNO3 → Zn(NO3)2 + X + H2O
(b) Zn + dil.HNO3 → Zn(NO3)2 + Y + H2O
Identify X and Y and write balanced equations.
 
38. Account for the following :
(a) Transition metals and majority of their compounds act as goodcatalysts.
(b) From element to element, actionoid contraction is greater thanlanthanoidcontraction
 
39. Explain the steps of preparation of potassium dichromate?
 
40. What is the lanthanoid contraction? What are its causes and consequences? 
 
41. Account for the following :
 
(a) La(OH)3 is more basic than Lu(O)H3
(b) Zn2+ salts are white.
 
(c) Cu(I) compounds are unstable in aqueous solution and undergodisproportination.
 
42. Describe the oxidising action of potassium dichromate with following. Writeionic equations for its reaction with.
(a) Iodide ion (b) Iron (II) (c) H2S.
 
43. What happens when
(a) thiosulphate ions react with alkaline KMnO4.
(b) ferrous oxalate reacts with acidified KMnO4.
(c) sulphurous acid reacts with acidified KMnO4
Write the chemical equations for the reactions involved.
 
44. (a) Deduce the number of 3d electrons in the following ions :  Fe3+, Cu2+ and Sc3+.
(b) Why do transition metals form alloys.
(c) Write any two characteristics of interstitial compounds.
 
45. How do you account for the following?
(a) With the same d-orbital configuration (d4), Cr2+ is a reducing agentwhile Mn3+is an oxidising agent.
(b) The actinoids exhibit a larger number of oxidation states than the corresponding members in the lanthanoid series.
(c) Most of transition metal ions exhibit characteristic colours in aqueoussolutions.

 

Please click on below link to download CBSE Class 12 Chemistry D And F Block Elements Question Bank Set B

Unit 8 The d- and f-Block Elements CBSE Class 12 Chemistry Worksheet

The above practice worksheet for Unit 8 The d- and f-Block Elements has been designed as per the current syllabus for Class 12 Chemistry released by CBSE. Students studying in Class 12 can easily download in Pdf format and practice the questions and answers given in the above practice worksheet for Class 12 Chemistry on a daily basis. All the latest practice worksheets with solutions have been developed for Chemistry by referring to the most important and regularly asked topics that the students should learn and practice to get better scores in their examinations. Studiestoday is the best portal for Printable Worksheets for Class 12 Chemistry students to get all the latest study material free of cost. Teachers of studiestoday have referred to the NCERT book for Class 12 Chemistry to develop the Chemistry Class 12 worksheet. After solving the questions given in the practice sheet which have been developed as per the latest course books also refer to the NCERT solutions for Class 12 Chemistry designed by our teachers. After solving these you should also refer to Class 12 Chemistry MCQ Test for the same chapter. We have also provided a lot of other Worksheets for Class 12 Chemistry which you can use to further make yourself better in Chemistry.

Where can I download latest CBSE Practice worksheets for Class 12 Chemistry Unit 8 The d- and f-Block Elements

You can download the CBSE Practice worksheets for Class 12 Chemistry Unit 8 The d- and f-Block Elements for the latest session from StudiesToday.com

Are the Class 12 Chemistry Unit 8 The d- and f-Block Elements Practice worksheets available for the latest session

Yes, the Practice worksheets issued for Unit 8 The d- and f-Block Elements Class 12 Chemistry have been made available here for the latest academic session

Is there any charge for the Practice worksheets for Class 12 Chemistry Unit 8 The d- and f-Block Elements

There is no charge for the Practice worksheets for Class 12 CBSE Chemistry Unit 8 The d- and f-Block Elements you can download everything free

How can I improve my scores by solving questions given in Practice worksheets in Unit 8 The d- and f-Block Elements Class 12 Chemistry

Regular revision of practice worksheets given on studiestoday for Class 12 subject Chemistry Unit 8 The d- and f-Block Elements can help you to score better marks in exams

Are there any websites that offer free Practice test papers for Class 12 Chemistry Unit 8 The d- and f-Block Elements

Yes, studiestoday.com provides all the latest Class 12 Chemistry Unit 8 The d- and f-Block Elements test practice sheets with answers based on the latest books for the current academic session