Chapter wise -SAMPLE PAPER FOR COORDINATION COMPOUNDS

 

SUBJECT: CHEMISTRY          SAMPLE PAPER FOR  COORDINATION COMPOUNDS

TIME:   3 HOURS            MM:70 General Instructions: Read the following instructions carefully. a) There are 35 questions in this question paper with internal choice. b) SECTION A consists of 18 multiple-choice questions carrying 1 mark each. c) SECTION B consists of 7 very short answer questions carrying 2 marks each. d) SECTION C consists of 5 short answer questions carrying 3 marks each. e) SECTION D consists of 2 case- based questions carrying 4 marks each. f) SECTION E consists of 3 long answer questions carrying 5 marks each. g) All questions are compulsory. h) Use of log tables and calculators is not allowed SECTION A ( MCQs) 1. Which of the following compounds has tetrahedral geometry? (a) [Ni(CN)4]2- (b) [Pd(CN)4]2- (c [PdCl4]2- (d) [NiCl4]2- 1 2. K2[Fe(CN)6] is a/an (a) double salt (b) complex salt (c) acid (d) base 1 3. The number of possible isomers for the complex |Co(C2O4)2 (NH3)2| (a) 1 (b) 2 (c) 3 (d) 4 1 4. According to Werner’s theory of coordination compounds (a) Primary valency is ionisable (b) Secondary valency is ionisable (c) Primary and secondary valencies are lonisable (d) Neither primary nor secondary valency is ionisable 1 5. The ligand N(CH2CH2NH2)3 is (a) bidentate (b) tridentate (c) tetradentate (d) pentadentate 1 6. Among the following which are ambidentate ligands? (i) SCN– (ii) NO−3 (iii) NO−2 (iv) C2O2−4 (a) (i) and (iii) (b) (i) and (iv) (c) (ii) and (iii) (d) (ii) and (iv) 1 7. Among the following ions which one has the highest paramagnetism ? (a)[Cr(H2O)6] 3+ (b) [Fe(H2O)6] 2+ (c) [Cu(H2O)6] 2+ (d) [Zn(H2O)6] 2+ 1 8. The complex ion which has no d-electrons in the central metal atom is (a) [MnO4]– (b) [Co(NH3)6]3- (c) [Fe(CN)6]3- (d) [Cr(H2O)6]3+ 1 9. The correct IUPAC name of the coordination compound K3|Fe(CN)5NO| is (a) Potassium pentacyanonitrosylferrate (II) (b) Potassium pentacyanonitroferrate (II) (c) Potassium nitritopentacyanoferrate (IV) (d) Potassium nitritepentacynanoiron (II) 1 10. Correct formulae of tetraaminechloronitroplatinum (IV) sulphate can be written as (a) [Pt(NH3)4 (ONO) Cl]SO4 (b) [Pt(NH3)4Cl2NO2]2 (c) [Pt(NH3)4 (NO2) Cl]SO4 (d) [PtCl(ONO)NH3(SO4)] 1 11. |Pt(NH3)4| |CuCl4| and |Cu(NH3)4||PtCl4| are known as (a) hybridization isomers. (b) coordination isomers (c) linkage isomers (d) polymerization isomers 1 12. The name of the linkage isomer of |C0(NH3)5NO2|Cl2 will be (a) pentaammonotrocobalt (II) chloride (b) pentaaminenitrochloridecobaltate (III) (c) pentaamminenitritocobalt (III) chloride (d) pentanitrosoamminechlorocobaltate(III) 1 13. Which of the following complex species is not expected to exhibit optical isomerism? (a) [Co(en) (NH3)2Cl2]+ (b) [Co(en)3]3+ (c)[Co(en)2Cl2] (d) [Co(NH3)3Cl3] 1 14. EDTA is used for the estimation of (a) Na+ and K+ ions (b) Cl– and Br– ions (c) Cu2+ and Cs+ ions (d) Ca2+ and Mg2+ ions 1 (A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion. (B) Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion (C) Assertion is correct but Reason is incorrect (D) Assertion is incorrect but Reason is correct 1 15 Assertion : [Ti(H2O)6]3+ is coloured while [Sc(H2O)6]3+ is colourless. Reason : d-d transition is not possible in [Sc(H2O)6]3 as it has no unpaired electron. 1 16 Assertion : [Fe(CN)6]3– is weakly paramagnetic while [Fe(CN)6]4– is diamagnetic. Reason : [Fe(CN)6]3– has +3 oxidation state while [Fe(CN)6]4– has +2 oxidation state. 1 17 Assertion: Chelates are less stable than ordinary coordination compounds. Reason: Chelates can be formed by bidentate ligands. 1 18 1.      Assertion : Linkage isomerism arises in coordination compounds containing ambidentate ligand. Reason : Ambidentate ligand has two different donor atoms donating simultaneously. 1 SECTION : B 19 On the basis of crystal field theory,write the electronic configuration for d4 ion if Δo >P.Explain 2 20 When a coordination compound CrCl3.6H2O is mixed with AgNO3 ,2 moles of AgCl are precipitated per mole of the compound. Write structural formula & IUPAC name of the complex. OR Discuss the nature of Bonding in metal carbonyls. 2 21 What is meant by stability of a coordination compound in solution? State the factors which govern stability of complexes. Or Giving a suitable example for each, explain the following : (i) Linkage isomerism (ii) Ambidentate ligand 2     1+1 22. The formula Co(NH3) 5CO3Cl could represent a carbonate or chloride. Write structures and names of possible isomers. 2 23. [Co (NH3)6] +3 is an inner orbital complex whereas [Ni(NH3)6] +2 is an outer complex. 2 24. What is crystal field splitting energy? What are the various factors affecting CFSE. 2 25. What is spectrochemical series? Explain the difference between a weak field ligand and a strong field ligand. 2 SECTION :C 26 a.Which complex ion is formed when undecomposed AgBr is washed with hypo solution in photography?Give reaction. b. Why only transition metals are known to form pi complexes? 1+2 27 A complex is prepared by mixing CoCl2 and NH3 In the molar ratio of 1:4, 0.1M solution of this complex was found to freeze at -0.372°c. what is the formula of the complex ? Given that molal depression constant of water (kf)=1.86c/m 3 28. a.Calculate the over all complex dissociation equilibrium constant for the[ cu(NH3)4]2+ ion , given that β for this complex is 2.1 x(10)13? b. Predict the number of unpaired electrons in the square planar [Pt(CN)4] 2- ion. 2+1 29. a. CuSO4.5H2O is blue in colour while CuSO4 is colouress. Why ? b. Magnetic moment of [MnCl4] 2- is 5.92BM. Explain giving reason . 2+1 30 a.Explain Coordination isomerism with example. b. Write down the applications of coordination compound Or a) Describe the shape and magnetic behaviour of following complexes : (i) [CO(NH3)6]3+ (ii) [Ni(CN)4]2-                  (At. No. Co = 27, Ni = 28) 1+2   1.5+1.5 SECTION :D 31 Read the given passage and answer the questions that follows. Negative ion or Neutral molecule which bound to the metal ion by secondary valency is called as ligand. In complex , metal ion acts as Lewis acid and ligand act as Lewis base. Ligands are classified according to number of electron pair in them. The ligand which can donates one e pair to the metal atom is called Unidentate ligand . The ligand which can donate two electron pair to the Metal ion is called didentate ligand. The ligand in which two or more coordination sites are there is called polydentate ligand. 75 Polydentate ligand forms cyclic structure with metal ion and form Chelate. i)   Give an example of unidentate neutral ligand. ii)   What are lewis acids and lewis bases. iii)  How didentate and Ambidentate ligands are different ? Give example. 1+1+2 32 Read the passage given below and answer the following questions: Coordination compounds are formulated and named according to the IUPAC system. Few rules for naming coordination compounds are: (I) In ionic complex, the cation is named first and then the anion. (II) In the coordination entity, the ligands are named first and then the central metal ion. (III) When more than one type of ligands are present, they are named in alphabetical order of preference with any consideration of charge.   ANSWER THE FOLLOWING QUESTIONS: -   (i) The IUPAC name of [Ni(CO)4] is (ii) The IUPAC name of the complex [Pt(NH3)3Br(NO2)Cl]Cl is (iii) As per IUPAC nomenclature, the name of the complex [Co(H2O)4(NH3)2]Cl3 is (iv) Which of the following represents correct formula of dichloridobis(ethane-1,2-diamine)cobalt(III) ion? 1+1+1+1 SECTION :E 33 (a) Account for the different magnetic behavior of hexacyanoferrate (III) and hexafluoroferrate (III). (b) (i) What type of isomerism is shown by the complex                 [Cr (H2O)6]Cl3 ? (ii) On the basis of CFT , write the electronic configuration for d4 ion if Δ0 > P . (iii) Write the hybridization and shape of [CoF6] 3- . Or a.(i) Write down the IUPAC name of the following complex : [Cr(NH3)2CI3(en)]Cl (en = ethylenediamine) (ii) Write the formula for the following complex : Pentaamminenitrito-o-Cobalt (III) b.Define the following terms; (a) Homoleptic complex ( b) Hetroleptic complex ( c) Coordination sphere 2+3         2+3 34 a. Which of the following is more stable complex and why? [Co(NH3)6]3+ and [Co(en)3]3+ b. Why are low spin tetrahedral complexes not formed? c. Give evidence that [Co(NH3)5Cl]SO4 and [Co(NH3)5SO4]Cl are ionization isomers? OR a. Compare the following complexes with respect to their shape, magnetic behaviour and the hybrid orbitals involved : (i) [CoF4]2- (ii) [Cr(H2O)2(C2O4)2]– (iii) [Ni(CO)4] (Atomic number : Co = 27, Cr = 24, Ni = 28) 1+2+2         1.5+2+1.5 35 For the complex [Fe(en)2Cl2], Cl, (en = ethylene diamine), identify (i) the oxidation number of iron, (ii) the hybrid orbitals and the shape of the complex, (iii) the magnetic behaviour of the complex, (iv) the number of geometrical isomers, (v) whether there is an optical isomer also, show and (vi) name of the complex. (At. no. of Fe = 26) OR a. With proper diagram explain crystal field splitting for octahedral complexes. b. What are t2g and eg orbitals ? Explain. ½+1+ 1/2+1+1+1       3+2