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Low densitysystems . The molecular weight properties of a polymer may vary over the life cycle of a material as the polymer progresses through stages such as raw material, molding, sterilization, and storage. a) Number average molecular weight polyethylene: the most extensively produced polymer. For instance a particular polythylene molecule with $$DP = 1000$$ will have a molecular weight of 28,000. Figure 1. The rate of reactions of most organic compounds are A. Weight-average molecular weight: Mw = ZwxMx = NXMX wx = wt fraction of polymer chains having molecular weight, Mx = - ZNXMX. Chain growth involves initiation using an initiator and propagation of the polymer as a chain with a propagating chain end. Two experimentally determined values are common: $$M_n$$, the number average molecular weight, is calculated from the mole fraction distribution of different sized molecules in a sample, and $$M_w$$, the weight average molecular weight, is calculated from the weight fraction distribution of different sized … c) Isentropic Knowledge of the molecular weight of polymers is very important because the physical properties of macromolecules are affected by their molecular weight. • Application: adhesives and coatings. The properties of the polymers depend on the distribution of molecular weights. SEC-MALS determines molecular weight from 200 g/mol to 1 billion g/mol. Click here to solve MCQ 1) Which ocular DDS has the largest particle size among these? If loading fails, click here to try again, The polymer used in orthopedic devices and in controlled drug release is, The number average molecular mass and mass average molecular mass of a polymer are respectively 30,000 and 40,000. __________ consist of individual polymers with varying molecular weights. Secondary Structure . a) True 10) Which GRDDS technique required external assistance? A polymeric molecules possess the molecular weight _____ a) Different b) Fixed c) That cannot be determined d) May be determined View Answer . One technique is viscometry. The molecular weight of a particular polymer molecule is a product of the degree of polymerization and the molecular weight of the repeating unit. Neoprene or polychloroprene is a synthetic rubber that is flexible at different temperatures, has good resistance to oil and substantial stability to the chemical. Skempton's … All Rights Reserved. Outline! Theory: Viscosity is an internal property of a fluid that offers resistance to flow. ∞ is the tensile strength of the polymer with molecular weight of infinity. Molecular weight of a polymer is equal to the molecular weight of the repeat unit multiplied by the degree of polymerisation. The EPA hopes this technical manual will: (1) assist the chemical manufacturer or importer in determining whether the PMN substance is a polymer as defined by the polymer exemption rule, (2) guide the manufacturer or importer in determining whether the … High … These chains are compounded from multiple small molecules that can alter the mechanical behavior of the polymer and skew its molecular weight. Very slow B. 5. What is the molecular weight of poly vinyl chloride (PVC), if its degree of polymerisation is 800? This thermoplastic has an extremely wide range of applications, being therefore one of the most produced polymers. At lower molecular weight, the polymer chains are loosely bonded by weak van der Waals forces and the chains can move easily, responsible for low strength,althoughcrystallinityispresent.Incaseoflargemolecularweight PDF unavailable: 33: Determination of Molecular Weight of Polymers (Contd.) No. Paul J. Flory, Principles of Polymer Chemistry, 1st Edition 1953 Cornell University The intrinsic viscosity is defined by. Our testing, insight and advice can assist you in your decision making process and help to ensure the integrity of the product. c) Number median molecular weight Polymers Class 12 Chemistry MCQs Pdf. Weight average molecular weight _____ on … View Answer, 5. d) Adiabatic Crosslink … Because polymeric materials do not consist of strictly identical molecules, but instead are a mixture of many species having different values of $$DP$$, the … Also, this page requires javascript. Polymers MCQs: MCQs test on 'Polymers' with answers, Test: 1, Total Questions: 15 Which of the following statements is not correct for fibres? Several methods utilized to characterize polymers give average molecular weights that depend on the molecular weight distribution as well as the number average molecular weight. The size of the polymer is best discussed in terms of molecular weight. Compounds having same molecular formula but differ in structural formula are called A. Polymer B. Monomer C. Isomer D. Allotropes View Answer. References & Notes. The molar mass distribution of a … Because of this, polymer molecular weights are usually given as averages. Answer: a Explanation: When polymerisation takes place, the growing polymeric chains are terminated at different sizes of molecules. What are Polymers? oligomer: a low molecular weight polymer in which the number of repeating units is approximately between two and ten. phenol with. D. Sinking approach. Correct Answer. High molecular weight is achieved early on and polymer is A number average molecular weight is obtained by methods that solely depend on the colligative properties of polymer solutions. Learn Polymer Technology MCQ questions & answers are available for a Chemical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. If you leave this page, your progress will be lost. You have not finished your quiz. a) Number average molecular weight Adapted from G. Odian, Principles of Polymerization, 4 th edition, Willey … The word “polymer” has been derived from the Greek words 'poly' and 'meros', implying many parts, and refers to a characterizing feature of polymeric materials – their chain like structure. Electric resistivity . Introduction Synthetic polymers are polydisperse to varying degrees in a variety of ways. 1. Fibres possess high tensile strength and … It can also determine molecular size – the rms radius, or radius of gyration R g – from 10 nm to 500 nm and beyond. What physical property of a material that refers to the rate of heat flow … Number-average molecular weight: Nx = # moles of polymer chains having molecular weight, M, Weight-average molecular weight: ZNXMX wx = wt fraction of polymer chains having molecular weight, Mx = Degree of polymerization: DPn = NXMX SNXMX "1-c c = extent of conversion of functional groups Polydispersity index: M, Critical extent of reaction: 2 1 pi v Average degree of … Secondary Structure . View Answer, a) Number average molecular weight Condensation polymerization involves the splitting out of a small molecule , usually water and (1) the presence of a carbon-carbon double bond; (2) the presence of a carbon-carbon It is represented by η. Students can solve NCERT Class 12 Chemistry Polymers MCQs Pdf with Answers to know their preparation level. View Answer, 3. Which compound form linear polymer due to H-bond? Molecular mass of the polymer (Mp) is equal to the multiplication of molecular mass of the monomer (Mm) and degree of polymerization (n). 2 Polymers are long chain molecules produced by linking small repeat units (monomers) together There are many ways to link different types of monomer to form polymers Polymers exhibit very different physical properties compared to the monomers, dependent on the length of the polymer chains The … 11) Zinc oxide and titanium oxide used in which GRDDS approach? Determination of molecular weight of polymers by visometry 1. View Answer, 2. Please wait while the activity loads. Once you are finished, click the button below. © 2011-2021 Sanfoundry. High-molecular-weight polymers with weight-average molecular weight M w ∼ 10 5 were successfully obtained when excess 2,2′-dimethoxybiphenyl was used in the presence of several equivalents of AlCl 3 catalysts (entry 13, Table 1). MCQs Of Polymer chemistry 1. Chapter 4 Polymer solutions 4.1 Introduction Solution: any phase containing more than one component. Polymer Molecular Weight Units. The Ostwald method is a simple method for the measurement of viscosity, in which viscosity … Any items you have not completed will be marked incorrect. (Q2) : define first order … 1. B. where c is the concentration of the solute and η 0 the viscosity of the solvent. Weight distribution and weight average In the case of MCQ/S, photoreduction forms macroradicals that recombine causing an increase in the molecular weight. The size of the polymer is best discussed in terms of molecular weight. Answer: Option D. 16. Molecular Weight : The glass transition temperature is also affected by the molecular weight of the polymer (Fig. The polydispersity index of polymer will be It is due to the internal friction of molecules and mainly depends on the nature & temperature of the liquid. While small molecules of the same elemental composition all exhibit the same molecular weight, polymer chains exhibit different characteristics. Chemistry (SPPU) M3-21 Synthetic Organic Polymers Q. Calculate the osmotic pressure associated with 50.0 g of an enzyme of molecular weight 98,000 g/mol dissolved in water to give 2600 mL of solution at 30.0 o C. (a) 0.484 torr (b) 1.68 torr (c) 1.96 torr (d) 2.48 torr (e) 3.71 torr 16. a) True Neoprene . The shape of the polymer molecule (molecular architecture) will be inﬂuenced naturally by the nature of the repeating unit and the manner in which these units are linked together. b) Osometry Which of the following belongs to the class of natural polymers?Options: Viscometry average molecular weight. The __________ is always higher than the number average molecular weight, except for the special case when they are equal if all of the polymers have the exact same molecular weight. View Answer, 7. a) Symmetry Then the molecular weight and intrinsic viscosity relationship is defined. The molecular weight of a particular polymer molecule is a product of the degree of polymerization and the molecular weight of the repeating unit. b) False Number-average molecular weight: Nx = # moles of polymer chains having molecular weight, Mx. Polymer degradation is a change in the properties—tensile strength, color, shape, or molecular weight—of a polymer or polymer-based product under the influence of one or more environmental factors, such as heat, light, and the presence of certain chemicals, oxygen, and enzymes. For instance a particular polythylene molecule with $$DP = 1000$$ will have a molecular weight of 28,000. Degree of polymerization: 1 DPn = 1-c c = extent of conversion of functional groups. T g is increased with the molecular weight. Knowing the Mark–Houwink parameters and the molecular weight of one of the polymers allows one to find the molecular weight of the other polymer using a GPC. b) Weight average cation weight ethylene glycol and … Polymers: Molecular Weight and its Distribution 1. Clear Q. The number average molecular mass and mass average molecular mass of a polymer are respectively 30,000 and 40,000. a) Natural b) Synthetic c) Semisynthetic d) Artificial 16 Ʃ Ʃ Formula is used for calculating _____ molecular weight. To practice all areas of Pulp and Paper, here is complete set of 1000+ Multiple Choice Questions and Answers. • Electronic device process: LED, FET, PV, Memeory etc. … At high temprature the enzymes denatures because enzymes are made of globular proteins .and proteins are made from combination of many amino acids so amoung linkage of this amino acids there is bond called peptide bond so at high temprature the peptide breaks down and the whole polypeptide chain breaks into simple once to amino acid so thus enzyme becomes denature.as … Ubbelohde viscometer is coomonly used viscometer to determine the relative viscosity of polymer solution. And MALS detectors only require annual calibration. Neoprene is rapidly … Contents • Introduction • Determination of molecular weight • Polymer solutions • Viscometry • References 3. A is some constant, and M is the molecular weight. Z average molecular weight or Z average molar mass is the third power average molar mass. Also, the molecular weights of two different polymers in a particular solvent can be related using the Mark–Houwink equation when the polymer-solvent systems have the same intrinsic viscosity: = Knowing the Mark–Houwink parameters and the molecular weight of one of the polymers allows one to find the molecular weight of the other … c) Weight average anion weight What is the name of the hidden part? Your email address will not be published. Polymers are not restricted to monomers of the same chemical composition or molecular weight and structure. Number distribution and number average molecular weight (Mn)! (gas, liquid or solid) Polymer solution is important: • Classical analyses of polymers are conducted on dilute solutions size exclusion chromatography osmometry, viscometry light scattering. Give an example of biodegradable polymer. Join our social networks below and stay updated with latest contests, videos, internships and jobs! View Answer, 6. (1) A high molecular weight molecule built from a large number of simple molecules is called a (A) Monomer (B) Isomer (C) Polymer (D) Tautomer. _ Engg. As polymer molecules have different chain lengths, the average molecular mass will depend on … Introduction • In simple compounds there is some definiteness about the molecular weight, hence we can say the … ... C. Low molecular weight D. All of these. ; The number average molecular weight divided by the molecular mass of a repeat unit is known as the number average degree of polymerization, whereas the weight average divided by the molecular … c) Monodisperse A de… b) Polydispersity The organic compounds having very high molecular weight are called A. Carboxylic acids B. Ketones C. Aldehydes D. Polymers View Answer. Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Free PDF Download of CBSE Chemistry Multiple Choice Questions for Class 12 with Answers Chapter 15 Polymers. For instance, polymerizing styrene, a monomer, under suitable reaction conditions, results in the polymer polystyrene (Figure 1). One such method is vapour phase __________ that indirectly measures vapor pressures of polymer solutions. a) Monodisperse b) Polydispersity c) Cellulose chain d) Synthetic polymer polyester: a polymer with a COOR repeating unit. The polydispersity index of the polymer is This makes determining a … Which one of the following is not a condensation polymer? Sol: (b) The amino acid sequence. Copolymers and higher mer polymers also need to be characterized for molecular composi- tion as a function of molecular weight. Dependence of mechanical strength on polymer molecular weight. 73. The molecular weight of a polymer is determined by the chemical structure of the monomer units, the lengths of the chains and the extent to which the chains are interconnected to form branched molecules. Correct Answer. Many methods are available for measuring viscosity of polymer solution. Floating approach B. Muco-adhesive approach. The polymer sample contains chains of varying lengths, therefore, its molecular mass is always expressed as an average. Students can solve NCERT Class 12 Chemistry Polymers MCQs Pdf with Answers to know their preparation level. 4. The polydispersity index of the polymer is, The plastic household crockery is prepared, using. 14 In mixed aromatic/aliphatic solvents, the polymer … It is given by the formula: Here, M z represents the Z average molecular weight. The species which can best serve as an initiator for the cationic Chemistry 5861 - Polymer Chemistry 3 d) D) Mw bar/Mn bar ≥ 1 is Polydisperse General Molecular Weight Expression & Mz bar and Mv bar 1) 2) a) 3) a) b) II M bar = ΣNiMi (a+1) / Σ N iMi a A Higher Order MW, called the Z average, is closely related to processing D. Thermal conductivity. Professionals, Teachers, Students and Kids Trivia Quizzes to test your knowledge on the subject. A. It is a way of determining the molecular mass of a polymer. You need a extent of reaction of 1 for this reaction to yield high molecular weight polymers. MCQ quiz on Polymers multiple choice questions and answers on Polymers MCQ questions quiz on Polymers objectives questions with answer test pdf. polymerization is: Thermosetting polymer, Bakelite is formed by the reaction of b) Weight average PDF unavailable: 32: Determination of Molecular Weight of Polymers (Contd.) Answer: Option C. 17. Determination of molecular weight of polymers by viscometry Presented by: Udhay Kiron 13305017 2. Determine the viscosity average molecular weight of a polymer. A. Dacron B. Neoprene C. Melamine D. Glyptal 2. The polydispersity index of polymer will be The molecular weight is related to the glass transition temperature by the Fox–Flory Equation: T g =T g, ∞ ̶ (K/M n) (Fox-Flory Equation) where T g, ∞ is the glass transition temperature at the molecular weight of infinity, and K is … A sample of a high polymer consist of 10% by weight of a macromolecule of molecular weight 10000 and 90% by weight of a macromolecule with molecular weight 100000, then its weight average molecular mass will be (a) 52000 (b) 85000 (c) 91000 (d) 89000. Ans: the heat amount of heat required to raise the temperature of one gram of the polymer one degree Celsius is called the heat capacity. Some natural polymers are composed of one kind of monomer. Block copolymers and polymer mixtures also offer signiﬁcant challenges to evaluate their molecular weight distribution. d) Weight average quinon weight It can be expressed in different units such as poise and pascal second (Pa s = N s m-2). What physical property of a material refers to the amount of weight gain (%) experienced in a polymer after immersion in water for a specified length of time under a controlled environment? As the molecular weight increases, the compound is more grease-like, and, if the MW is greater than about 6000, PEG is a white solid. The molecular weight of polymer that is determined by viscometry is MV i.e. A __________ depicted as Mn, Let Ni equal the number of the molecules or moles or other calculated of number of molecules with mass M, or a calculated of mass such as D.P. c) Cellulose chain The shape of the polymer molecule (molecular architecture) will be inﬂuenced naturally by the nature of the repeating unit and the manner in which these units are linked together. Question 5. PDF unavailable: 34: Structural Analysis of Polymers by Spectroscopic Methods: PDF unavailable: 35: Amorphous and Crystalline State : Tg and Tm: PDF unavailable: 36: Amorphous and … d) Synthetic polymer _____is not a classified form of conjugated proteins. (a) In aromatic solvents, the polymer molecular weight decreases with increasing basicity of the solvent. Stock Preparation & Additives for Papermaking, Calculations of Wood, Paper & Other Materials, here is complete set of 1000+ Multiple Choice Questions and Answers, Prev - Pulp & Paper Questions and Answers – Condensation Polymers, Next - Pulp & Paper Questions and Answers – Nomenclature, Electrical Machines Questions and Answers – Transformer Phasor Diagram, Electrical Machines Questions and Answers – Equivalent Circuit of Transformer, Chemical Process Calculation Questions and Answers, Engineering Chemistry I Questions and Answers, Chemical Engineering Questions and Answers, Polymer Engineering Questions and Answers, Pulp & Paper Questions and Answers – Wood Chips Preparation and Handling at the Pulp Mill, Pulp & Paper Questions and Answers – Wood Chip Measurement, Pulp & Paper Questions and Answers – Basic Optical Tests of Paper, Pulp & Paper Questions and Answers – Paper Machine, Pulp & Paper Questions and Answers – Basic Paper Properties, Pulp & Paper Questions and Answers – Internal Sizing, Pulp & Paper Questions and Answers – Sulphite Liquor Analysis, Pulp & Paper Questions and Answers – Wood Moisture Content and Density, Pulp & Paper Questions and Answers – Specific Types of Paper, Pulp & Paper Questions and Answers – General Grades of Paper, Polymer Engineering Questions and Answers – Distribution of Molecular Weight in Linear Polycondensation, Pulp & Paper Questions and Answers – Mechanical Properties of Paper. . b) False The properties of the polymers depend on the distribution of molecular weights. Free PDF Download of CBSE Chemistry Multiple Choice Questions for Class 12 with Answers Chapter 15 Polymers. The polymers produced in polymerization reactions … Very fast … 131 Kevlar polymer in the structure of chain contains _ (a) c) Monodisperse AR, MCQ; Q. a) Number average b) Weight average c) Viscosity average d) Z-average 17 Which of the following is not a characteristic property LED? Determination of Molecular Weight of Polymers (Contd.) Download CBSE Class 12 Chemistry Polymers MCQs Set A in pdf, Chemistry chapter wise Multiple Choice Questions free, Q.1 Which is not true about polymers?Options: (a) Polymers do not carry any charge(b) Polymers have high viscosity(c) Polymers scatter light(d) Polymers have low molecular weightAnswer=DQ.2. Polymer Molecular Weight Distributions 11 Samples of synthetic polymers always contain polymer chains with a range of chain lengths One way to describe the length of the polymer chains is in terms of an average molecular weight, i.e the average of all the chain lengths in the sample HOWEVER…. Viscosity is defined as the measure of the opposing force of material to flow. growing polymer molecule; (2) crosslink the polymer; (3) network the polymer; (4) form a thermosetting polymer ___ 19. • Certain high molecular weight polymers once considered eligible for submission under the 1984 exemption are not eligible for this exemption. When the number of monomers is very large, the compound is sometimes called a high polymer. View Answer. 15 Silk is an example of _____ polymer. b) Number mean molecular weight The source of Taq polymerase used in PCR is a : isomers of glucose that differ in configurations at carbons one and four (C-1 and C-4), isomers of glucose that differ in configuration at carbon one (C-1). Sol: (d) Complete proteins. Buoyant unit weight equals the saturated density (A) Multiplied by unit weight of water (B) Divided by unit weight of water (C) Plus unit weight of water (D) Minus unit weight of water. The change of moisture content of soils, changes the (A) Value of the angle of repose (B) Amount of compaction required (C) Cohesive strength of soil (D) All the above. This structure is formed by developing chemical links between a number of monomers or repeating units. View Answer: Answer: Option C. Solution: 13. Sanfoundry Global Education & Learning Series – Pulp and Paper. (d) Interaction with molecular chaperons. C. Magnetic approach . A. This set of Pulp and Paper Multiple Choice Questions and Answers (MCQs) focuses on “Molecular Weight of Polymers”. b) Weight average p-Block Elements MCQs | Question – Paper 1. 11. Z Average Molecular Weight. a) 50000 b) 51600 c) 49200 d) 50800 … The Living World; Biological Classification; Plant Kingdom; Morphology of Flowering Plants; Anatomy of Flowering Plants; Cell - The unit of Life; Cell Cycle and Cell Division; Transport in Plants; Mineral Nutrition; Photosynthesis in Higher Plants; Respiration in Plants; Plant Growth and Development; Reproduction in … the molecular weight growth is slow. The mass average molecular mass & number average molecular mass of a polymer are respectively 40,000 and 30,000. What is the average molecular weight of an amino acid residue in a protein? a) Monodisperse View EC_MCQ_3.pdf from CS,MATH IT101 at Singhad College Of Nursing , Pune. Step-growth polymerization! B. 12. Polymer Science and Engineering Lecture 3 - Molecular Weight Averages and Distributions January 22, 2001 Reading: Sperling, Chapter 3. Polymers and Molecular Weight GPC On Tour, Barcelona, 28th February 2012 1 . A. Dielectric strength. M.C.Q. The word polymer designates an unspecified number of monomer units. Chemistry MCQs for Class 12 Chapter Wise with Answers PDF Download was Prepared Based on Latest Exam Pattern. 3. The polymer molecular weight is affected by several variables, such as (a) the type of solvent, (b) the monomer and cobalt concentration, (c) the concentration of the aluminum alkyl, (d) the polymerization temperature and (e) the monomer conversion. The unit of molecular weight of polymer is either kg/mol or g/mol. The advantage to determine molecular weight by … Remove Filters; Clear Question Attempted × Botany. Because of this, polymer molecular weights are usually given as averages. Polymer Technology MCQ question is the important chapter for … Mechanistic studies found that the AlCl 3 could selectively coordinate with the methoxy groups in the monomer to deactivate its reaction with acyl … The number of monomers in a chain is called the degree of polymerization. The chains in a sample may differ in, for example, molecular weight, degree of long or short-chain branching, stereostructure or composition (either grossly, as with copolymers, or slightly, as with end group or foreign moieties incorporated in the chain during … For example, shown in the interrelation between molecular weight and strength for a typical polymer. Molecular weight has an important effect on the mechanical properties of polymer, more especially above the glass transition temperature. Please visit using a browser with javascript enabled. C. Water absorption. d) Polydispersity A. H2O B. NH3 C. a) Weight average molecular weight View Answer, 4. Conclusion Upon irradiation of MCQ/S copolymer film by light with λ > 380 nm in air, the CQ structure in the copolymer was transformed mainly … This change in properties is often the result of bond breaking in the polymer backbone (chain scission) which may occur at the … The mass average molecular mass & number average molecular mass of a polymer are respectively 40,000 and 30,000. If this activity does not load, try refreshing your browser. $\overline {M_w}$ is the weight average molecular weight. Clear Chapter Wise. copolymer or higher mer polymers with various degrees of structural randomness further complicate a complete description of the molecular ensemble.