Principles of Qualitative Analysis and Bioinorganic Chemistry — DU B.Sc (hons) Chemistry Previous Year Question Papers

I. (a) Draw the percentage oxygen saturation curves for Haemoglobin. Explain how a change influences it? a) A test tube contains an aqueous solution of cr(Ill) and Al(Ill) ions. Suggest reagent/reagents to separate the cations. Give confirmatory tests to dete-ct the two cations with equations. (c) ,Identify the ions that are detected by the following reagents. Also, write the chemical reactions involved. ` (i) Dimethyl glyoxime (ii) Zirconium nitrate 2. (a) Distinguish between essential and non-essential elements. Draw the dose-response curve for an essential element and a toxic element. (b)Howarenitrateandnitritei`onstestedwhenpresenttogetherinamixtur??Giveequations to support your answer. (c) Define Therapeutic Index. Why is cisplatin a preferred anti-cancer drug in contrast to transplatin? Explain the mechanism of action. 3i. (a) What are ionophores? How are they different from ion channels? Give one example. (b) Which specialized proteins are used for the transport of iron in the bloodstream? Can. free iron be transported in the bloodstream? (c) A metal `M' is capable ofexistihg in two oxidation states, +Ill and+V. An aqueous solution of its salt in the lower oxidation state gives a white precipitatie on the addition of concentrated ammonia, whi'ch, however, disappears on adding hydrochloric acid. `X'is a compound of `M' in thehigheroxidationstate.ItisusedtodetectMn(II).Identify`M'and`X'andgivethereact;ons. 4. (a) Explain the mechanism .of conduction of nerve impulses? Draw a well-labeled action potential graph. (b) An aqueous solution of sodium sulphide cannot be used to separate Group IIA and Group 118. Explain. Why are cadmium ions fiequently missed in group 11 analysis? (c) Why NH4Cl is added with NH40H in Group Ill ofcaLtion Ana`lysis? ` (d) Explain the role of cytochrome~C-oxidase in humans? Where is it present? 5. (a) What do you understand by colripartmentalization in the context of a living cell? Explain the calcium ion pump diagrammatically. (b) Give cdnfirmatory tests for Borate and Fluoride ions in a salt mixture. Why are they called interfering ions? (c) What are the special properties of Zinc that make it an excellent biocatalyst? What is the role of the enzyme carbonic anhydrase? What is the coordination number and geometry of zinc ions in carbonic anhydrase? 6. (a) Give the chemistry behind the fl.ame test for cations? What colour do Ca(II) and Ba(II) ions show i`n the flame?. (b) What is chelation therap)r? What special properties Should a ligand possess so that it can-be used in this therapy? (c) Why do Pb(II) ions sometimes precipitate in Group I as well as Group 11 in qualitative mixture analysis for cations? Give one confirmatory test for the detection of pb(II) ions in Group