In a polymer sample, 30% of molecules have a molecular mass of 20,000, 40% have 30,000, and the rest- 60,000. What is the weight average molecular mass= of the polymer?

(1) 40,300

(2) 30,600

(3) 43,333

(4) 50,400

Which of the following statement is correct?

(1) Vinyon is a copolymer of vinyl chloride and vinyl acetate

(2) Saran is a copolymer of vinyl chloride and vinylidene chloride

(3) butyl rubber in a copolymer of isobutylene and isoprene

(4) all are correct

The reagent that is used for converting propylene to polypropylene is: 

1. TiCl₃ + K/THF

2. TiCl₄ + Al(C₂H₅)₃

3. TiCl₃ + (CH₃)₂Mg

4. TiCl₄ + CH₃(CH₂)₃Al

Which of the following polymer can be used for lubrication and as an insulator? 

(1) SBR

(2) PVC

(3) PTFE

(4) PAN

Polyacrylonitrile, characterized by the  repeating unit is made from the monomer: 

1. ${\mathrm{CH}}_2=\mathrm{CHCN}$

2. ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CN}$

3. ${\mathrm{HOCH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_3$

4. ${\mathrm{CH}}_3\mathrm{CH}=\mathrm{CHCN}$

The monomer used for the manufacture of PVC is obtained by the addition of -

1. ${\mathrm{Cl}}_2$ to ethylene

2. ${\mathrm{Cl}}_2$ to acetylene

3. HCl to ethylene

4. HCl to acetylene in presence of ${\mathrm{Hg}}^{2+}$ salts

The number average molecular mass and mass average molecular mass of a polymer are respectively 30,000 and 40,000. The polydispersity index of the polymer is

1. < 1

2. > 1

3. 1

4. 0

True statements regarding polymers are: 

a. Polymers have a low molecular weight.

b. Polymers have high viscosity.

c. Polymers scatter light.

d. Polymers do not carry any charge.

1. a, b and c

2. a, b and d

3. b, c and d

4. a, c and d

Which of the following is not correctly matched?

(1) Nylon-6, 6

${\left( \mathrm{O}\right)}_{}$
$\left|\right|$
$-\mathrm{NH}-({\mathrm{CH}}_2{)}_6-\mathrm{NH}-\mathrm{CO}-({\mathrm{CH}}_2{)}_4-\mathrm{C}-n$

(2) Neoprene

${\left({\mathrm{CH}}_2 - \mathrm{C} = \mathrm{CH} - {\mathrm{CH}}_2 -\right)}_{}$
$|$
$\mathrm{Cl}\mathrm{n}$

(3) PMMA

(4)Terylene

Which /are correct about spandex?

(I) It is a polyurethane
(II) It is a flexible polymer
(III) It is a polymer of toluene 2, 6 di isocyanates, and glycol
(IV) lt is a polymer of ammonium carbamate

(1) I, II, III

(2) I, II, IV

(3) III, II, IV 

(4) I, II, III, IV