1. Ka Is Acid Dissociation Constant of the Conjugate Acid Of

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1. Ka is acid dissociation constant of the conjugate acid of: a) CO2 b) NH3 c) NH4 d) None of these B 2. pH linked biosensors are applicable to any system in which: a) Change in pH during chemical reaction takes place b) No change in pH during chemical reaction takes place c) Chemical reaction do not affect Ph d) None of these a 3. The immobilized enzyme on the ph sensor will decompose the analyte to produce: a) Calcium ions b) Hydrogen ions c) Nitrogen ions d) None of these b 4. Penicillin converts into Penicilloate in the presence of the catalyst: a) B-Lectamose b) Glucose oxidose c) Urease d) None of these a 5. Glucose converts into Gluconic acid in the presence of catalyst: a) B-Lectamose b) Glucose oxidose c) Urease d) None of these b 6. Urea converts into Ammonium in the presence of catalyst: a) B-Lectamose b) Glucose oxidose c) Urease d) None of these c 7. Creatinine converts into creatine in the presence of catalyst: a) B-Lectamose b) Glucose oxidose c) Urease d) None of these d 8. In the presence of catalyst adenine deaminase, Adenosine converts into: a) Creatine b) Inosine c) Penicilloate d) Gluconic acid b 9. High level of oxalate in urine is an indicator of: a) Kidney stones b) Low blood sugar c) High blood pressure d) High blood sugar a 10. Which of the following metabolites can be detected using a CO2 sensor: a) Urea b) Oxalates c) Penicillin d) Phenylalanine a 11. Which of the following can be detected using a Ammonia sensor: a) Gluconic acid b) Oxalates c) Penicillin d) Phenylalanine d 12. Debye-Huckle theory is related to: a) Ion activity b) Lithography c) Ion transport kinetics d) None of these c 13. Part of the electrode double layer containing charges in increasing disordered manner in the outward direction into the solution is called: a) Helmholtz plane b) Diffused part c) Both a) and b) d) none of these b 14. In inner Helmholtz layer potential changes: a) Linearly with distance b) Exponentially with distance c) Logarithmically with distance d) None of these a 15. In outer diffused layer potential changes: a) Linearly with distance b) Exponentially with distance c) Logarithmically with distance d) None of these b 1. If selectivity coefficient for Hydroxide in the presence of F- ion electrode is 0.1, for a concentration of Hydroxide 10 times higher than fluoride would give a response: a) Three times that of fluoride alone b) Two times that of fluoride alone c) Ten times that of fluoride alone d) None of these B *For a calibrated ISE , the calibration slope was +29.6 mV/decade in a 0.01 M solution. In a 0.001 M calcium chloride solution, the cell potential was -20.1 Mv while the potential in a mixed solution containing 0.01 CaCl2 and 0.1 M NaCl was -19.8 Mv. 2. Ionic strength of pure solution will be: a) 0.001M b) 0.002 M c) 0.003M d) 0.004M C 3. Ionic strength of mixed solution will be: a) 0.100M b) 0.103M c) 0.106M d) 0.112M B 4. Ion activity of pure calcium ion will be: a) 0.0001M b) 0.0004M c) 0.0008 M d) 0.0009M C 5. Selectivity coefficient of Ca+2 ions in the presence of Na+ will be: a) 0.0805 b) 0.008 c) 0.103 d) 0.705 D .

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Oh Ho Oh Oh Oh Oh O Ho Ch3o N N H O Ho Oh Oh Oh Oh O Ho Ch3o N N
CHEM1611 2008-J-11 June 2008 Marks • Quinine has long been used for the treatment of malaria. For an intramuscular 4 injection, quinine is reacted with gluconic acid. Structures and molar masses for these substances are shown below. HO N H OH OH O CH O 3 HO OH N OH OH quinine gluconic acid molar mass 324.41 g mol –1 molar mass 196.16 g mol –1 Quinine and gluconic acid can undergo an acid-base reaction to form a salt, or a condensation reaction to form an ester. One molecule of each substance is required for the transformation, and a 160.0 mg dose of quinine gluconate is equivalent to a 100.0 mg dose of quinine. By determining the molar mass of the product formed, or otherwise, determine whether the product formed is an ester or a salt. The two possible products, and their molar masses, are shown below. HO OH OH O N H HO CH3O H O OH OH N Salt: formed by proton transfer from acid group on gluconic acid to quinine -1 amine, with no loss of mass. Formula C 26 H26 N2O9 and molar mass 520.57 g mol OH OH O HO O OH OH N H CH3O N Ester: formed from acid group on gluconic aicd and –OH group on quinine with -1 elimination of water. Formula C 26 H24 N2O8 and molar mass 502.56 g mol ANSWER CONTINUES ON THE NEXT PAGE CHEM1611 2008-J-11 June 2008 100.0 mg of quinine corresponds to: ̡̭̳̳ ̊̉̉.̉Ɛ̊̉ ̌ ̧ number of moles = Ɣ = 3.083 × 10 -4 mol ̡̭̯̬̲ ̡̭̳̳ ̌̋̍.̍̊ ̧ ̭̯̬ ̊ 160.0 mg of the salt product corresponds to: ̡̭̳̳ ̊̏̉.̉Ɛ̊̉ ̌ ̧ number of moles = Ɣ = 3.074 × 10 -4 mol ̡̭̯̬̲ ̡̭̳̳ ̎̋̉.̎̐ ̧ ̭̯̬ ̊ 160.0 mg of the ester product corresponds to: ̡̭̳̳ ̊̏̉.̉Ɛ̊̉ ̌ ̧ number of moles = Ɣ = 3.184 × 10 -4 mol ̡̭̯̬̲ ̡̭̳̳ ̎̉̋.̎̏ ̧ ̭̯̬ ̊ As the dosages are the same, it must be the salt which is being administered.
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ProvisionalChapter chapter 14 The PossibilityPossibility of of Recovering Recovering of Hydroxytyrosolof Hydroxytyrosol from fromOlive Milling Wastewater by Enzymatic Bioconversion Olive Milling Wastewater by Enzymatic Bioconversion Manel Hamza and Sami Sayadi Manel Hamza and Sami Sayadi Additional information is available at the end of the chapter Additional information is available at the end of the chapter http://dx.doi.org/10.5772/64774 Abstract This chapter discusses an innovative approach to obtain liquid fractions from olive mill wastewater (OMW) rich in hydroxytyrosol. The method is based on bioconversion combined with membrane separation techniques. An enzymatic bioconversion of three types of OMW was tested. TheS total volumes of OMW are 15 and 40 L. The reaction was monitored in mechanically stirred systems for 2 h at 50°C. Maximum hydroxytyr‐ osol concentrations of about 1.53, 0.83 and 0.46 g/L in the presence of 5 IU Aspergillus niger β‐glucosidase per milliliter from North OMW and South OMW were procured by two different olive millings, which are milling super press (MSP) and milling continuous chain (MCC), respectively. Enzymatic pretreatment was followed by two tangential flow membrane separation stages, microfiltration (MF) and ultrafiltration (UF). The ultrafiltration permeate was concentrated by evaporation at 45°C for 2 h. The latter exhibited a chemical oxygen demand (COD) level of 48.44 g/L. The UF permeate dehydration increased the hydroxytyrosol concentration to 7.2 g/L. A new natural product that contains some minerals beneficial to health and devoid of heavy metals or chemicals was obtained by this innovative work which describes an environmentally friendly process at pilot‐scale.
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