The monomer units of silicons a water repellant, acid resistant and heat resistant polymer is:

1. Si                         

2. SiO₂

3. R₂SiO                   

4. None of these

A polymer of acrylonitrile is called:

1. Saran

2. Orlon

3. Dacron

4. Tetron

Which one of the following pairs is not correctly matched?

1. Terylene—condensation polymer of terephthalic acid and ethylene glycol

2. Teflon—thermally stable cross-linked polymer of phenol and formaldehyde

3. Perspex—a homopolymer of methyl methacrylate

4. Synthetic rubber —a copolymer of butadiene and styrene

Natural silk and artificial silk differ in one respect that one of them contains:

(1) N                     

(2) S

(3) P                       

(4) none of these

Among the given options , the one that is not fibre is: 

1. Terylene.

2. Nylons.

3. Polyacrylonitrile.

4. Polychloroprene.

Which of the following cannot be grouped as polyolefins?

(1) Polystyrene                     

(2) Polypropene

(3) Polystyrene                     

(4) Polyoxyethene

The monomer units of PTFE are:

(1) Cl₂CH-CH₃

(2) F₂C=CF₂

(3) F₃C-CF₃

(4) FClC=CF₂

Among the given polymers, an example of homopolymer is:

1. Bakelite

2. Nylon-6,6

3. Terylene

4. Neoprene

Number average molecular mass (${\overline{\mathrm{M}}}_{\mathrm{n}}$) and mass average
mol. mass (${\overline{\mathrm{M}}}_{\mathrm{w}}$)of synthetic polymers are related as:

(1) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ < ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(2) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ > ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(3) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ = ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(4) M_n > M_w

Which of the following is wrong?

1. PMMA is called plexiglass

2. PTFE is called teflon

3. SBR is called natural rubber

4. LDPE is called low density polyethylene