Organic Chemistry C. Polymer

1. Natural rubber is a polymer of – [Jharkhand P.C.S. (Pre) 2013, U.P.P.C.S. (Pre) 1992]

(a) Butadiene
(b) Ethylene
(c) Isoprene
(d) Styrene

Correct Answer: (c) Isoprene

Solution:Polymerization is the process of joining together a large number of small molecules to make a very large molecule. The small molecules from which the polymer is constructed are called monomers, and products of the polymerization process are called polymers. Natural rubber is the natural polymer of isoprene. Isoprene is a colorless liquid made by destructive distillation of petroleum.

2. Natural rubber is a polymer of – [66th B.P.S.C. (Pre) (Re. Exam) 2020 ,65th B.P.S.C. (Pre) 2019]

Correct Answer: (a) Isoprene

Solution:Polymerization is the process of joining together a large number of small molecules to make a very large molecule. The small molecules from which the polymer is constructed are called monomers, and products of the polymerization process are called polymers. Natural rubber is the natural polymer of isoprene. Isoprene is a colorless liquid made by destructive distillation of petroleum.

3. Which of the following is not a natural polymer? [U.P.P.C.S. (Mains) 2015, U.P.U.D.A./L.D.A. (Pre) 2001]

(a) Wool
(b) Silk
(c) Leather
(d) Nylon

Correct Answer: (d) Nylon

Solution:Wool, silk, leather are natural polymers but nylon is not a natural polymer.

4. Which one of the following is a natural polymer? [U.P.P.C.S. (Pre) 2017]

(a) Bakelite
(b) Silk
(c) Kevlar
(d) Lexan

Correct Answer: (b) Silk

Solution:Wool, silk, leather are natural polymers but nylon is not a natural polymer.

5. Which of the following is not a natural polymer? [U.P. Lower Sub. (Pre) 2009]

(a) Ghee
(b) Starch
(c) Protein
(d) Cotton

Correct Answer: (a) Ghee

Solution:Ghee is not a polymer while the rest all are natural polymers.

6. Which among the following is a constituent of natural silk? [U.P. P.C.S. (Pre) 2023]

(a) Potassium
(b) Magnesium
(c) Nitrogen
(d) Phosphorus

Correct Answer: (c) Nitrogen

Solution:Silk is a naturally occurring protein fiber produced from the larvae of the moth to build their cocoons. This fiber is used for the commercial production of silk fabric. Nitrogen is a constituent element of natural silk.

7. Cellulose and starch both are made up of – [Uttarakhand P.C.S. (Pre) 2016]

(a) (+) – glucose
(b) (–) – fructose
(c) Both (a) and (b) given above
(d) (+) – galactose

Correct Answer: (a) (+) – glucose

Solution:Cellulose is the most commonly found organic compound, biopolymer, and polysaccharide on the earth. Each of these molecules contains several hundred to thousands of glucose molecules in the form of an insolculated homopolymer series. Starch plants have structural polysaccharides that contain two types of homopolysaccharide molecules made of glucose cells – about 10 to 30 percent amylose and about 70 to 90 percent amylopectin molecules.

8. The most abundantly found organic compound in nature is – [U.P.P.C.S. (Mains) 2014, U.P.P.C.S. (Mains) 2012]

(a) Glucose
(b) Fructose
(c) Sucrose
(d) Cellulose

Correct Answer: (d) Cellulose

Solution:Cellulose is a form of carbohydrate. It is a polysaccharide consisting of a linear chain of several hundred to many thousand of β-linked D-glucose units. It is the chief constituent of cell walls in living organisms. Wood is mostly cellulose, making cellulose the most abundant type of organic compound on the earth. Its purest natural form is cotton.

9. To which of the following chemical groups – Cellulose belongs? [Uttarakhand P.C.S. (Pre) 2021]

(a) Carbohydrates
(b) Proteins
(c) Lipids
(d) Nucleic acids

Correct Answer: (a) Carbohydrates