MCQOPTIONS
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MCQOPTIONS
This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Polymer Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What happens to overall rate of catalyzed photo-polymerization, when the initiator concentration is quadrupled? |
| A. | doubled |
| B. | quadrupled |
| C. | tripled |
| D. | remains same |
| Answer» B. quadrupled | |
| 2. |
What is the expression for rate of initiation in catalyzed photo-polymerization? ( I0 and φ are the intensity of incident light and number of pairs of chain radicals formed per quantum of light absorbed, respectively and ε be the molar absorption coefficient ) |
| A. | 2φεI0[I] |
| B. | φεI0[M] |
| C. | 2φεI0[M] |
| D. | φεI0[I] |
| Answer» B. φεI0[M] | |
| 3. |
What has the terms kd[I] in the overall rate equation of uncatalyzed photo-polymerization been replaced by? |
| A. | intensity of light radiation absorbed |
| B. | intensity of incident light |
| C. | number of pairs of chain radicals formed per quantum of light absorbed |
| D. | monomer concentration |
| Answer» B. intensity of incident light | |
| 4. |
WHAT_HAPPENS_TO_OVERALL_RATE_OF_CATALYZED_PHOTO-POLYMERIZATION,_WHEN_THE_INITIATOR_CONCENTRATION_IS_QUADRUPLED??$ |
| A. | doubled |
| B. | quadrupled |
| C. | tripled |
| D. | remains same |
| Answer» B. quadrupled | |
| 5. |
Which of the following is not true about photo-sensitizer in photo-polymerization? |
| A. | easily gets excited on exposure to light |
| B. | carries energy absorbed to initiator or monomer |
| C. | helps in both catalyzed and uncatalyzed polymerizations |
| D. | gets excited and decomposes to give radicals |
| Answer» E. | |
| 6. |
What is the expression for rate of initiation in catalyzed photo-polymerization? ( I0 and φ are the intensity of incident light and number of pairs of chain radicals formed per quantum of light absorbed, respectively and ε be the molar absorption coefficient )$ |
| A. | 2φεI<sub>0</sub>[I]  |
| B. | φεI<sub>0</sub>[M]  |
| C. | 2φεI<sub>0</sub>[M]  |
| D. | φεI<sub>0</sub>[I]  |
| Answer» B. ‚âà√¨‚àö√∫‚âà√≠¬¨¬µI<sub>0</sub>[M]¬¨¬®‚Äö√тĆ | |
| 7. |
Photo-activation allows the use of a wide range of chemicals as polymerization initiators in comparison to the thermal catalyzed process. State true or false. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 8. |
Which of the following initiator system works on the mechanism of photo-activation? |
| A. | hydrogen halide |
| B. | nitrobenzene complexes |
| C. | hydrogen sulphide |
| D. | oxalate complex of transition metals |
| Answer» D. oxalate complex of transition metals | |
| 9. |
How does the overall rate of uncatalyzed photo-polymerization vary, when the monomer concentration is quadrupled, rest all the terms remain same? |
| A. | two fold increase |
| B. | eight fold increase |
| C. | remains same |
| D. | two fold decrease |
| Answer» C. remains same | |
| 10. |
What does the intensity of active radiation absorbed in uncatalyzed photo-polymerization, not depend on? |
| A. | thickness of reaction mixture |
| B. | intensity of incident radiation |
| C. | monomer concentration |
| D. | none of the mentioned |
| Answer» B. intensity of incident radiation | |
| 11. |
What has the terms kd[I] in the overall rate equation of uncatalyzed photo-polymerization been replaced by? |
| A. | intensity of light radiation absorbed |
| B. | intensity of incident light |
| C. | number of pairs of chain radicals formed per quantum of light absorbed |
| D. | monomer concentration |
| Answer» B. intensity of incident light | |
| 12. |
What is the mechanism of uncatalyzed photo-initiation of polymerization, when light of specific wavelength falls on monomer? |
| A. | monomer directly decomposes to give radicals |
| B. | monomer generates excites species by absorbing light quanta and then decompose into radicals by homolysis |
| C. | photo-initiator is added to monomer and decomposes to radicals by photolysis |
| D. | all of the mentioned |
| Answer» C. photo-initiator is added to monomer and decomposes to radicals by photolysis | |