Coordination Compounds quiz

The oxidation state of Fe in K4[Fe(CN)6] is:

EDTA is a:

Which ligand is ambidentate?

[Ni(CN)4]2- has the shape and magnetic behaviour:

The number of ions produced in solution by [Co(NH3)5Cl]Cl2 is:

Which of the following is the strongest field ligand?

[Co(NH3)5(NO2)]Cl2 and [Co(NH3)5(ONO)]Cl2 are examples of:

The hybridisation of Co in [CoF6]3- is:

The relation between tetrahedral and octahedral splitting is:

The complex used in cancer chemotherapy is:

What are homoleptic and heteroleptic complexes? Give one example of each. (2 marks)

Why do tetrahedral complexes not show geometrical isomerism? (2 marks)

Why are low-spin tetrahedral complexes rarely observed? (2 marks)

What is ionisation isomerism? Give an example. (2 marks)

Why is [Ti(H2O)6]3+ coloured while [Sc(H2O)6]3+ is colourless? (2 marks)

Write the formula of (i) tetraamminediaquacobalt(III) chloride (ii) potassium tetrachloridonickelate(II). (2 marks)

How is EDTA used to estimate hardness of water? (2 marks)

Name the metal present in chlorophyll, haemoglobin and vitamin B12. (2 marks)

What is meant by the chelate effect? (2 marks)

Why is [Co(NH3)6]3+ an inner orbital complex while [CoF6]3- is an outer orbital complex? (2 marks)

Calculate the spin-only magnetic moment of [MnCl4]2- (Mn2+, d5, high spin) and of [Cr(NH3)6]3+ (d3) (sqrt(35) = 5.92, sqrt(15) = 3.87). (3 marks)

0.02 mol of a complex CrCl3.6H2O gives 0.04 mol of AgCl with excess AgNO3. Write the formula of the complex and identify the type of isomerism shown by the series of CrCl3.6H2O compounds. (3 marks)

Calculate the CFSE of a d6 ion in a strong octahedral field and in a weak octahedral field in terms of Delta_o (ignore pairing energy in the expression but state the number of paired electrons). (3 marks)

A complex absorbs light of wavelength 600 nm. Calculate the crystal field splitting energy in kJ mol^-1 (h = 6.626 x 10^-34 J s, c = 3 x 10^8 m/s, NA = 6.022 x 10^23 mol^-1). (3 marks)

Calculate the oxidation number and coordination number of the central metal in (i) [Fe(C2O4)3]3- (ii) [Co(en)2Cl2]+ (iii) [Ni(CO)4]. (3 marks)

Read the passage and answer the questions. Three compounds of the formula CoCl3.xNH3 were treated with excess AgNO3. CoCl3.6NH3 gave 3 mol AgCl, CoCl3.5NH3 gave 2 mol and CoCl3.4NH3 gave 1 mol per mole of compound. The last compound exists in green and violet forms. (i) Write the formulae of the three complexes. (ii) Explain the results using Werner's theory. (iii) What type of isomerism do the green and violet forms show? (5 marks)

Read the passage and answer the questions. Cisplatin, cis-[PtCl2(NH3)2], is a widely used anticancer drug, whereas its trans isomer is inactive. The complex is square planar. (i) Draw both isomers. (ii) What type of isomerism is this? (iii) What is the hybridisation of Pt(II) in this complex? (5 marks)

Read the passage and answer the questions. Aqueous copper sulphate is blue. Adding excess ammonia gives a deep blue solution, and adding potassium fluoride to aqueous CuSO4 gives a green precipitate. (i) Name the complex responsible for the deep blue colour. (ii) Explain the change in colour in terms of ligand field strength. (iii) Which ligand is stronger, NH3 or H2O? (5 marks)

Read the passage and answer the questions. [Fe(H2O)6]3+ has five unpaired electrons, while [Fe(CN)6]3- has only one. Both have Fe in the +3 oxidation state. (i) Explain the difference using crystal field theory. (ii) Calculate the magnetic moment of each. (iii) Which is an inner orbital complex? (5 marks)

Read the passage and answer the questions. Haemoglobin contains a complex of iron with a porphyrin ring that carries oxygen in blood. Carbon monoxide binds to iron about 200 times more strongly than oxygen. (i) Why is CO poisonous? (ii) What type of ligand is the porphyrin ring? (iii) Name one other biologically important coordination compound. (5 marks)

Explain Werner's theory with examples. Draw the structures of the complexes formed from CoCl3 and NH3 and show primary and secondary valencies. (6 marks)

Explain the structural isomerism in coordination compounds with examples, and draw a chart classifying all types of isomerism. (6 marks)

Explain stereoisomerism in coordination compounds with diagrams of geometrical and optical isomers. (6 marks)

Explain the valence bond theory of coordination compounds with orbital diagrams for one octahedral, one square planar and one tetrahedral complex, and state its limitations. (6 marks)

Explain crystal field theory for octahedral complexes with a splitting diagram. Explain high-spin and low-spin complexes, the spectrochemical series and the colour of complexes. (6 marks)