Natural Rubber MCQs Questions Answers

By: Prof. Dr. Fazal Rehman | Last updated: May 29, 2025

1. : In ____ the cis-poly isoprene is present.
(A) Gutta rubber
(B) Guayule rubber
(C) Percha rubber
(D) Hevea rubber

2. : The filtered latex is fed into long rectangular tanks of ____ deep when producing the smoked rubber.
(A) 30cm
(B) 2m
(C) 50cm
(D) 1m

3. : The latex is reacted with formic acid, vertical partition plates are inserted and left undisturbed for ____ during the production of smoked rubber.
(A) 16 hours
(B) 14 hours
(C) 15 hours
(D) 13 hours

4. : After applying the ___ stress, the temporary deformation of rubber takes place.
(A) 600e.u
(B) 500e.u
(C) More than 600e.u
(D) More than 500e.u

5. : _____ is the reason of elasticity of rubber.
(A) Helix
(B) Octahedral
(C) Pentagonal bipyramidal
(D) Trigonal planar

6. : In soft ____ colored mass the rubber is coagulated.
(A) White
(B) Light yellow
(C) Yellow
(D) Light pink

7. : The coagulum is passed between two rollers of about ___ wide when producing the crepe rubber.
(A) 50cm
(B) 4mm
(C) 3mm
(D) 100cm

8. : The rubber sheets are hanged in smoked chambers at ______ to produce the smoked rubber.
(A) 40-50°C
(B) 20-30°C
(C) 30-40°C
(D) 10-20°C

9. : The mature leaves are grounded and heated about ____ in the solvent extraction process.
(A) 70°C
(B) 50°C
(C) 60°C
(D) 40°C

10. : _____ latex is diluted and filtered to remove suspended impurities.
(A) 15-20%
(B) 10-15%
(C) 5-10%
(D) 20-25%

11. : The sheets are hanged for about _________ in smoked chambers during the production of the smoked rubber.
(A) 1 day
(B) 4 days
(C) 3 days
(D) 2 days

12. : To extract _____ solvent extraction process is used.
(A) Gutta percha
(B) Smoked rubber
(C) Crepe rubber
(D) Guayule rubber

13. : With the ___ the filtered latex is treated when it is sent into the tanks.
(A) Poly isoprene
(B) Formaldehyde
(C) Acetaldehyde
(D) Acetic acid