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B.Sc. Semester 6 (Paper -14, Organic Chemistry) SET-1

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B.Sc. Semester 6 (Paper -14, Organic Chemistry) SET-1 B.Sc. Semester 6 (Paper -14, Organic Chemistry) SET-1 Full marks=60 I. Objective Question: (1x15=15) 1. Wave number is given by the formula (a) λ (b) 1/λ (c) λ 2 (d)1/ λ2 2. Hooke’s law for the vibration of a diatomic molecule may be represented as (a) F= kx (b) F= -kx (c) x= kF (d) ) x= -kF 3. Bathochromic effect is also called (a) Blue Shift (b) Red Shift (c) Green Shift (d) None of these 4. Broad, moderately intense absorbtion in the low frequency region suggests the presence of (a) Carboxylic acid (b) Amides (c) Amines (d)All of these 5. How many NMR signals would be given by (CH3)2CHCH2CH3 (a) 3 (b) 4 (c) 5 (d) 2 6. If a proton is linked to some electronegative atom via hydrogen bond, absorption in NMR will be (a) upfield (b) unchanged (c) downfield (d) None of theses 7. The number of asymmetric carbon atoms in a α–D-glucopyranose is (a) 3 (b) 4 (c) 5 (d) 2 8. The sugar that yields only glucose on hydrolysis (a) Lactose (b) Sucrose (c) Maltose (d) Fructose 9. All of the following monosaccharides give the same osazone except (a) Galactose (b) Glucose (c) Mannose (d) Fructose 10. Monomer of Neoprene is (a) Chloroprene (b) Isoprene (c) Isobutane (d) Isopentene 11. Adipic acid reacts with hexamethylene diamine to form (a) bakelite (b) Nylon-6,6 (c) Polyethylene (d) Teflon 12. Orlon is prepared by polymerization of (a) vinyl cynide (b) allyl alcohol (c) vinyl chloride (d) allyl chlride 13. Color lake formed by alizarin with Sn2+ ions (mordant) is (a) blue (b) red (c) violet (d) black 14. The water solubility of dyes can be increased by introducing (a) SO3Na groups (b) COOH groups (c) OH groups (d) All of these 15. A substance which appears orange absorbs the radiation in the range (nm) (a) 400-435 (b) 480-490 (c) 500-560 (d) 605-750 II. Very Short Answer Type Question (1x10=10) 1. What is Chromophore? 2. What is finger print region in IR spectroscopy? 3. What is coupling constant? 4. What is Nylon-66? 5. What are anomers? III. Short Answer Type Question: (7x5=35) 1. What is the principle difference between IR and UV spectroscopy? 2. How will you distinguish between the following pair of compounds with IR spectroscopy:- (a) Acetic acid and methyl acetate (b)Acetone and acetic acid (c)Ethyl alcohol and Dimethyl ether 3. What do you understand by chemical shift, equivalent and non- equivalent proton in NMR spectroscopy? 4. Give structure of the compound having molecular formula C3H3Cl3, consistent with following NMR data: (a) singlet δ 2.2, 2H (b) Singlet δ4.02, 2H. 5. Illustrate the various steps of Osazone synthesis from glucose. 6. Provide suitable explanation for the following:- (a) Fructose reduces Fehling’s solution and Tollen’s reagent although it contains keto group. (b)Relative configuration D is given to fructose even though it is laevorotatory. 7. What are addition and condensation polymers? Illustrate each one with a suitable example. B.Sc. Semester 6 (Paper -14, Organic Chemistry) SET-2 Full marks = 60 I. Objective Question (1x15=15) 1. Light is (a) Beam of α particles (b) Electromagnetic radiation(c) Beam of β particles (d) None of these 2. Which is not the auxochrome (a) OH (b) NH2 (c) OCH3 (d) NO2 3. Which substance is taken as a internal standard for NMR (a) Dimethylsilane (b) Tetramethylsilane (c) Trimethylsilane (d) Methylsilane 4. If the chemical shift on the δ scale is 4, that on τ scale it would be a) -6 (b) 1/ 4 (c) 6 (d) -4 5. Which of the following carbohydrate is not reducing sugar? a) Glucose (b) Sucrose (c) Fructose (d) Lactose 6. α–D-Glucopyranose is a) hemiacetal (b) hemiketal (c) acetal (d) ketal 7. Which of these products is not derived from cellulose? (a) Rayon (b) Insulin (c) Gum cotton (d) paper 8. Bakelite is obtained from: (a) Phenol and formaldehyde (b) Adipic acid and hexamethylene diamine (c) Neoprene (d) Chloroprene 9. Which of the following polymer contain nitrogen? (a) PVC (b) Teflon (c) Nylon (d) Terylene 10. Which of the following is a chromophore? (a) NO2 (b) SO3H (c) OH (d) COOH 11. Color of a compound is best explained by (a) Molecular orbital theory (b) Valence bond Theory (c) Witt’s Theory (d) None of these 12. Which dyes become linked to the fiber by chemical reaction? (a) Acid dyes (b) Direct dyes (c) Dispersed dyes (d) None of these 13. Which of the following cannot be detected with the help of UV absorption spectra? (a) Conjugation (b) Functional group (c) Geometrical isomerism (d) Optical isomerism 14. Which compound show maximum IR absorption frequency? (a) Acetone (b) Methyl ethyl ketone (c) cyclobutanone (d) Methyl vinyl ketone 15. Aldehyde group shows IR absorbtion frequency in the range of (a) 3300 cm-1 (b) 2650-2880 cm-1 (c) 3010-3100 cm-1 (d) 2850-2960 cm-1 II. Very Short Answer Type Question: (1x10=10) 1. What is auxochrome? 2. Give Lambert- Beer’s Law. 3. What is chemical shift? 4. Define the term epimers. 5. What is Dacron?. III. Short Answer Type Question: (7x5=35) 1. Describe in detail the various types of electronic transition which occur in UV spectroscopy with suitable example. 2. Discuss the various molecular vibrations in IR spectroscopy. 3. Explain shielding and deshielding of proton in NMR spectroscopy. 4. Explain splitting of signals in NMR spectra of Cl-CH2-CH2-CH2-Cl. 5. Illustrate the various steps of Killiani – fischer synthesis. 6. Explain why:- (a) Glucose contains aldehydic group still does not react with NaHSO3. (b) β-D- glycopyranose is most abundant naturally occurring aldohexaose. 7. What is Ziegler-Natta polymerization? Discuss its special importance in synthesis of addition polymers. B.Sc. Semester 6 (Paper - DSE 3, Industrial, Chemical and Environment) SET-1 Full marks=60 I. Multiple choice questions: (15 X 1 = 15) 1. Which of the following fuels have the highest calorific value? (a) Methane gas (b) Nitrogen Gas (c) Hydrogen gas (d) Bio- gas 2. Which of the following is not the characteristic of good fuel? (a)Easily transported and stored (b) Economical (c ) Smokeless (d) High ignition temperature 3. Which of the following is a conventional source of energy? (a) Wind energy (b) Natural gas (c) Sun (d) Bio-mass 4. Coal is a complex mixture of which elements? (a) Carbon (b) Hydrogen (c) Oxygen (d) All the above 5. The main constituent of petroleum gas is (a) Ethan (b) Butane (c) Propane (d) Methane 6. What is the ultimate source of energystored in fossil fuels? (a) Moon (b)Sea (c) Sun (d) Earth 7. Which fuel is not used in thermal power plant? (a) Coal (b) Uranium (c) Natural Gas (d) Fuel oil 8. Respiratory organs are protected from radiation with the help of (a) Respirator (b) Gas Mask (c) Helmets (d) Pneumatic suits (e) All 9. Which of the following can be stored in the soil (a) Sr-90 (b) Nb -95 (c) Zr – 95 (d) All 10. The Separation of a mixture of fission pruducts and analysisof their composition can be achieved by (a) Chromatography (b) Co- precipitation (c) Extraction (d) All 11. The Intermediate level radioactive wastes generally originate from (a) Sludges from Decontamination process (b) Fuel Processing (c) The later stage of solvent extraction (d) All 12. The radionuclides of high level wastes are segregated by (a) Coagulation (b) Precipitation (c) Ion exchange (d) All 13. Radioisotopes having high level activity can be disposed off by using (a) Reprocessing method (b) Immobilization method (c) Vitrification technique (d) All 14. Waste contaminated by radionuclides can be immobilized by (a) Heating (b) Tank solidification(c) using zeolites (d) Calcination (e) All 15. The disposal of radioactive wastes by dilution is generally adopted for (a) Low level waste (b) Intermediate level waste (c) High Level Waste (d) All II. Very Short Answer type Questions: (5 X 2 =10) 1. What is osmoregulation? 2. Give an example of decomposition taking place from abiotic process? 3. What are the main sources of sulphur in the atmosphere? 4. What are the main sources of phosphorous which play a key role in the biological system? 5. What do you mean by biosphere? III. Short Answers type questions: (7 x 5 =35) 1. What do you mean by water pollution? Classify and discuss the various type of water pollution? 2. What do you mean by (i) Biological Oxygen Demand (ii) Chemical Oxygen Demand? 3. Discuss the classification of Air Pollutants and also discuss the methods to minimize the Air Pollution? 4. What do you mean by Green house Effect? Mention two Green House Gases and discuss their effect? 5. What are the main causes for Ozone layer depletion? What are the effects of Ozone layer depletion? 5. Write short notes on any one of the followings: (a) Activated Sludge Process (b) Tricking Filtration 6. Discuss the sources, harmful effect and method of control of Oxides of carbon? 7. Discuss the various water quality parameters with their measurement unit? B.Sc. Semester 6 (Paper - DSE 3, Industrial, Chemical and Environment) SET -2 Full marks=60 I. Multiple Choice Question: (15 x 1 =15) 1. Which of the following are ecosystems: (a) Ocean (b) Mountain (c) Forest (d) Desert (e) All 2. The chief element present in the lithosphere are (a) Al and Si (b) Al and O (c) Si and N (d) Fe and Al 3. Hydrosphere includes (a) Oceans (b) Seas (c) Rivers and Lakes (d) Glaciers (e) All 4.
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