12th Standard Chemistry English Medium Coordination Chemistry Reduced Syllabus Important Questions With Answer Key 2021

12th Standard

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Chemistry

Time : 01:00:00 Hrs
Total Marks : 100

Multiple Choice Questions

15 x 1 = 15
1. The sum of primary valence and secondary valence of the metal M in the complex [M(en)2(Ox)]Cl isL

(a)

3

(b)

6

(c)

-3

(d)

9

2. An excess of silver nitrate is added to 100ml of a 0.01M solution of pentaaquachloridochromium(III)chloride. The number of moles of AgCl precipitated would be

(a)

0.02

(b)

0.002

(c)

0.01

(d)

0.2

3. Crystal field stabilization energy for high spin d5 octahedral complex is

(a)

-0.6$\triangle$

(b)

0

(c)

2(P-${ \Delta }_{ 0 }$)

(d)

2(P+${ \Delta }_{ 0 }$)

4. A complex in which the oxidation number of the metal is zero is

(a)

K4[fe(CN)6]

(b)

[Fe(CN)3(NH3)5]

(c)

[Fe(CO)5]

(d)

both (b) and (c)

5. The total number of electrons donated by ligands to platinum ion in [Pt(en)2CI2] is

(a)

8

(b)

10

(c)

12

(d)

14

6. Which of the following co-ordination compounds would exhibit optical isomerism?

(a)

Pemtaamminenitrocobalt (III) iodide

(b)

Diamminedichloropaltinum (II)

(c)

Tris-(ethylenediamine) cobalt (III) bromide

(d)

Transdicyanobis( ethylenediamine) chromium (III) chloride

7. Coordination compounds are stabilised by Chelate effect. Which among the following is the most stable complex?

(a)

[Fe(CN)6]3-

(b)

[Fe(Co)5]

(c)

[Fe(NH3)6]3+

(d)

[Fe(C2O4)3]3-

8. The oxidation number of nickel in complex ion, [NiCI4]2- is

(a)

+1

(b)

-1

(c)

+2

(d)

-2

9. In [Fe11(CN)6]4-, the central metal ion is

(a)

Fe

(b)

Fe2+

(c)

Fe3+

(d)

CN-

10. The coordination number of Ni(II) in [Ni(CN)4]2- is

(a)

2

(b)

4

(c)

5

(d)

0

11. Which of the following is not true about secondary valency?

(a)

It corresponds to the co-ordination number of metal

(b)

It is satisfied by negative ions or neutral molecule

(c)

They are non directional in nature

(d)

both (a) and (b)

12. A 'd' block metal ion has a magnetic moment of 1.732 BM. The number of unpaired electrons are

(a)

1

(b)

2

(c)

3

(d)

4

13. The ligand capable of coordinating in two or more ways with the central metal ion are called ___________ ligands.

(a)

didentate

(b)

tridentate

(c)

ambidentate

(d)

none of the above

14. According to crystal field theory, the bond between the ligand and central metal atom is_______________

(a)

Purely ionic

(b)

Purely covalent

(c)

Coordinate

(d)

50% ionic and 50% covalent

15. Primary valency corresponds to the ______________

(a)

oxidation state of the metal

(b)

co-ordination number

(c)

number of ligands

(d)

charge on the complex

1. 2 Marks

10 x 2 = 20
16. Write the formula for the following coordination compounds.
a) potassiumhexacyanidoferrate(II)
b) petacarbonyliron(0)
c) pentaamminenitrito −k−N-cobalt(III)ion
d) hexaamminecobalt(III)sulphate
e) sodiumtetrafluoridodihydroxidochromate(III)

17. Arrange the following in order of increasing molar conductivity
(i) Mg[Cr(NH3)(Cl)5]
(ii) Cr(NH3)5Cl]3[CoF6]2
(iii) [Cr(NH3)3Cl3]

18. Give an example of coordination compound used in medicine and two examples of biologically important coordination compounds

19. Draw all possible geometrical isomers of the complex [Co(en)2Cl2]+ and identify the optically active isomer.

20. Write a neutral molecule in which the central atom is Sp3 d2 hybridised.

21. Calculate the magnetic moment of [Fe(H2O)6]2+, if atomic number of Fe is 26.

22. What is a central atom or ion?

23. What are ligands?

24. Calculate the Oxidation number of
(i) iron in [Fe(CN)6]4-.
(ii) Cobalt in [Co(NH3)5CI)]2+.

25. Identify the ligand and the central metal in the Co-ordination compound. [Co(NH3)4Cl6]CI

1. 3 Marks

10 x 3 = 30
26. Give an example for complex of the type [Ma2b2c2] where a, b, c are monodentate ligands and give the possible isomers.

27. What is linkage isomerism? Explain with an example

28. Write briefly about the applications of coordination compounds in volumetric analysis

29. Classify the following ligand based on the number of donor atoms
a)NH3
b)en
c)ox2-
d) triaminotriethylamine
e) pyridine

30. Give the difference between double salts and coordination compounds.

31. How is magnitude of ${ \triangle }_{ 0 }$ affected by (i) nature of ligands (ii) oxidation state of metal ion.

32. Aqueous copper sulphate solution (blue) gives
(i) a green precipitate with aqueous potassium fluoride.
(ii) a bright green solution with aqueous potassium chloride. Explain these experimental results.

33. What is meant by unidentate, didentate and ambidentate Iigandst Give two examples for each.

34. Match the common name with formula and the IUPAC ligand name.

Common name Formula IUPAC ligand name
Bromide C2O42- Carbonato
Nitrate Br- Oxalato
hydroxide NO3- hydroxido
Carbonate OH- bromido
Oxalate CO32- nitrato
35. What are the limitations of VBT?

1. 5 Marks

7 x 5 = 35
36. Write the oxidation state, coordination number , nature of ligand, magnetic property and electronic configuration in octahedral crystal field for the complex K4[Mn(CN)6]

37. What are the postulates of valance bond theory? Give its limitations.

38. What is meant by stability of a co-ordination compound in solution? State the factors which govern stability of complexes.

39. What are the salient feature of crystal field theory?

40. How are metal carbonyls classified depending on the number of metal atoms?

41. Give the IUPAC name for the following compounds.
(i) [Ag(NH3)2]CI
(ii) K3[Fe(CN)5NO]
(ill) [Cr(PPh3)(CO)3]
(iv) [Ag(NH3)2]+
(v) [FeF6]4-

42. Give the structure for the following compounds.
(i) pentaamminechlorocobalt (III) ion
(ii) Triamminetrinitrito- k N cobalt (III)
(ill) tetraammineaquabromidooobalt(III)nitrate
(iv) Dichloridobisethane-1 )2-diamine) cobalt (lIl) chloride
(v) Tetraamminecopper (lI)sulphate