MCQOPTIONS
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MCQOPTIONS
This section includes 15 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. |
Which of the following polymer will not give grey colour when their pyrolytic vapours are tested with a strip of filter paper soaked in saturated solution of o- nitrobenzaldehyde in dilute NaOH? |
| A. | Nylon 6 |
| B. | Nylon 66 |
| C. | Nylon 12 |
| D. | Nylon 11 |
| Answer» C. Nylon 12 | |
| 2. |
What colour is obtained when a strip of filter paper soaked in saturated solution of o-nitrobenzaldehyde in dilute NaOH is held over the prylotic vapours of Nylon 6,6? |
| A. | grey |
| B. | black |
| C. | red |
| D. | yellow |
| Answer» C. red | |
| 3. |
A strip of cupric acid paper, freshly moistened with a dilute solution of benzidine in dilute acetic acid is held in the pyrolytic vapours of polymer A and a bright blue colouration is obtained. Which of the following could be polymer A? |
| A. | polyamide |
| B. | polyacryonitrile |
| C. | butyl rubber |
| D. | polyvinyl formal |
| Answer» C. butyl rubber | |
| 4. |
What colour is obtained if condensed pyrolyzate of polyacrylonitrile is made alkaline and boiled with ferrous sulphate followed by acidification? |
| A. | ruby-red |
| B. | prussian blue |
| C. | bright blue |
| D. | red-brown |
| Answer» C. bright blue | |
| 5. |
The aqeous extracts of some polymers when tested with chomotropic solution followed by addition of sulphuric acid and then heating to nearly 100 C gave dark violet colour. Which of the following cannot respond to this test? |
| A. | polyvinyl formal |
| B. | polyoxymethylenes |
| C. | urea-formaldehyde resisns |
| D. | polyacrylonitrile |
| Answer» E. | |
| 6. |
What colour is obtained when a drop of diphenylamine solution in concentrated sulphuric acid is added to the sample of cellulose nitrate in the absence of other oxidizing agents? |
| A. | deep blue |
| B. | yellow |
| C. | grey |
| D. | red |
| Answer» B. yellow | |
| 7. |
Which of the following do not respond to the Molisch test for carbohydrates? |
| A. | cellulose acetate |
| B. | viscose rayon |
| C. | cellulose nitrate |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 8. |
What colour is obtained by the pyrolytic vapours of butyl rubber on the filter paper freshly soaked in a solution obtained by dissolving yellow mercuric oxide in conc. sulphuric acid and water on boiling? |
| A. | bright yellow |
| B. | grey |
| C. | blue |
| D. | brown-yellow |
| Answer» B. grey | |
| 9. |
Which of the following rubbers turn the filter paper in ethereal solution containing p-dimethylamino benzaldehyde and hydroquinone and then moistened with a 30% solution of trichloroacetic acid in isopropanol grey with a yellow tinge? |
| A. | natural rubber |
| B. | silicones |
| C. | polychloroprenes |
| D. | butyl rubbers |
| Answer» D. butyl rubbers | |
| 10. |
A strip of filter paper dissolved in ethereal solution containing p-dimethylamino benzaldehyde and hydroquinone and then moistened with a 30% solution of trichloroacetic acid in isopropanol produces blue-violet colour in the presence of pyrolytic vapours of rubbers A and B. Which of the following pair represent rubbers A and B? |
| A. | natural rubber and butyl rubber |
| B. | styrene butadiene rubber and silicone rubber |
| C. | styrene butadiene rubber and natural rubber |
| D. | natural rubber and nitrile butadiene rubber |
| Answer» B. styrene butadiene rubber and silicone rubber | |
| 11. |
Which of the following rubber do not respond to trichloroacetic acid? |
| A. | isomerized rubber |
| B. | chlorinated rubber |
| C. | polysulphide rubber |
| D. | butyl rubber |
| Answer» C. polysulphide rubber | |
| 12. |
Which of the following rubbers when treated with trichloroacetic acid give pink-mauve melt and on dilution give grey-mauve precipitate? |
| A. | isomerized rubber |
| B. | acetone-extracted NR |
| C. | gutta percha |
| D. | all of the mentioned |
| Answer» E. | |
| 13. |
Polysulphide rubbers when treated with trichloroacetic acid imparted colour X, which turned to colour Ysolution on boiling and then colour Z precipitate on dilution. Which set of colours represent X, Y, Z, respectively? |
| A. | pink, red-brown, grey |
| B. | pink, ruby-red, rose-pink |
| C. | pink, red-brown, yellow |
| D. | pink, ruby-red, yellow |
| Answer» C. pink, red-brown, yellow | |
| 14. |
Which of the following does not give positive weber test of rubbers? |
| A. | natural rubber |
| B. | butyl rubber |
| C. | polyisoprene rubber |
| D. | styrene butadiene rubber |
| Answer» E. | |
| 15. |
A rubber polymer sample A is reacted with chromic acid solution and yields acetic acid solution. Compound A also gives positive Weber test. Which of the following is possibly A? |
| A. | 1,4-polyisoprenes |
| B. | butyl rubber |
| C. | nitrile butadiene rubber |
| D. | all of the mentioned |
| Answer» B. butyl rubber | |