Formaldehyde is a constituent of a number of polymers also called resins. These are non-volatile solids or semi-solids which are obtained from certain plants and also be synthesized in the laboratory.
(i) Name the main formaldehyde resins.
(ii) Mention the major components of these resins also called polymers.
(iii) Which out of these is useful in the manufacture of crockery?
(iv) Formaldehyde is obtained from plants. Similarly we obtain many useful things from plants. Is it worth to destroy plants for obtaining useful material ?

Polymers are giant molecules having very high molecular masses. Several of them occur in nature and find a variety of applications in our daily life and industry. Cellulose, starch, proteins, rubber etc. are some examples of natural polymers. Now answer the following questions:
(i)Does use of natural polymer cause pollution problems?
(ii) Name an inorganic natural polymer which is quite abundant in nature.
(iii) Name three polymers which are used in textile industry.
(iv) In what form is natural rubber usually used in rubber industry?

Synthetic polymers both addition and condensation have given a boom to our industry. These have made our lives very comfortable. But these are mostly nonbiodegradable and cause major pollution problems. Polythene bags, broken polythene pipes etc, are very difficult to be disposed off. Recently certain biopolymers have been developed which are better than synthetic polymers.
(i)Name certain biopolymers that are naturally occuring.
(ii) What is the nature of synthetic biopolymers ?
(iii) Name two synthetic biopolymers.
(iv)What is the value associated with the use of biopolymers?

Bakelites are phenol formaldehyde resins. These are both linear chains and cross-linked in nature. As a result of cross linking, bakelites become hard and brittle.
(i) What are the monomer units of bakelites?
(ii) What is the nature of the reaction that leads to polymerization?
(iii) What are the uses of both soft and hard bakelites?

Rubber is probably the most useful polymer which we come across. It is in fact, the backbone of the industry. It is present in rubber tree in the form of a colloidal suspension in water called latex. Chemically natural rubber is polyisoprene and is formed by polymerization of isoprene which is 2-Methyl-l,3-butadiene.
(i) Why is natural rubber quite soft?
(ii) How is vulcanisation of rubber carried?
(iii) Give anyone example of natural rubber.
(iv) What is the property of vulcanised rubber, which makes it's useful?

After the ban on plastic bags, students of a school decided to make people aware of the harmful effects of plastic bags on the environment and Yamuna River. To make the awareness more impactful, they organised a rally by partnering with other schools and distributed paper bags to vegetable vendors, shopkeepers and departmental stores. All the students pledged not to use polythene bags in the future to save the Yamuna River.
After reading the above passage, answer the following questions:
(i) What values are shown by the students?
(ii) What are bio-degradable polymers ? Give one example.
(iii) Is polyethene a condensation or an addition polymer?

Study the given passage carefully and answer the questions that follow:
Shalini studied a chapter on Polymers in school and came across the following paragraph: The durability, strength, low cost, water and chemicals resistance, welding properties, lesser'. energy, fewer atmosphere emissions and light weight are advantages of plastic bags. Shalini is confused as she has been reading in the
newspaper about the ban on the usage of plastic substances. She further finds that despite the durability, the use of these materials has presented mankind with serious waste disposal problem as these materials do not disintegrate by themselves. In view of this, certain polymers are being developed which are broken down rapidly by micro-organisms. Shalini feels relaxed that such kinds of biomaterials are being developed.
(i) Name the class of these useful polymers which do not harm the environment.
(ii) Give anyone example of these polymers and name its monomers.
(iii) Comment on the qualities of Shalini.

What is nylon?Write an equation for the chemistry involved contain alternate monomers of each type.What is the weight percent of ethylene in this copolymer.