A : Above all, they are cheaper and easier to process making them a viable alternative to metals.B : Polymers are essentially a long chains of hydrocarbon molecules.C : Today polymers as strong as metals have been developed.D : Metals are today being replaced by polymers in many applications.E : These have replaced the traditional chromium-plated metallic bumpers in cars.F : Many Indian Institutes of science and Technology run special programmes on polymer science.QUESTION 13bookmark_borderSelect the correct answerWhich of the following statementscan be the first statement of the paragraph?radio_button_uncheckedFradio_button_uncheckedAradio_button_uncheckedDradio_button_uncheckedEradio_button_uncheckedD

Which of the following statements about polymers is correct?

Read the text and answer the following questions with NO MORE THAN 2 WORDS.Why does man use metals still so much today when there are other materials, especially plastics, which are available? A material is generally used because it offers the required strength, and other properties, at minimum cost. Appearance is also an important factor. The main advantage of metals is their strength and toughness. Concrete may be cheaper, it is often used in buildings, but even concrete depends on its core of steel for strength.Plastics are lighter and more corrosion-resistant, but they are not usually as strong as metals. Another problem with plastics is what to do with them after use. Metals objects can be broken down and the metals are recycled after that but plastics can only dumped or burned.Not all metals are strong, however. Copper and aluminum, for example, are both fairly weak- but if they are mixed together, the result is an alloy called aluminum bronze, which is much stronger than either pure copper or pure aluminum. Alloying is an important method of obtaining whatever special properties are required: strength, toughness, resistance to wear, magnetic properties, high electrical resistance or corrosion resistance.The properties of a metal can be further improved by use of heat treatment which changes the properties of metals and alloys. For example, hardening is used to make metals harder. Tempering makes the softer and less brittle. Annealing is carried out to make a metal soft so that it can be machined more easily. In this way metallic materials can be produced to meet every kind of engineering specification and requirement.Methods of extracting, producing and treating metals are being developed all the time to meet engineering requirements. This means that there is an enormous variety of metals and metallic materials available from which to choose.1. Which material is used so popularly nowadays? 2. What does the word “them” in paragraph 2 refer to? 3. Which material is stronger than pure copper or aluminum? 4. What process can help change the properties of metals and alloys? 5. How many methods are developed to meet engineering requirements?

Which of the following is not true for resorbable polymer?1 pointThey degrade readily in bodyThey commonly consist of calciumThey can be thermosetting plasticThey are a chain of monomers

15In spite of being inexpensive, flexible, and simple to manufacture, _______ they derive from nonrenewable sources like oil, and the majority do not decompose in landfills.15 Mark For Review15Which choice completes the text so that it conforms to the conventions of Standard English?A) there are two issues related to synthetic polymers: B) two issues are related to synthetic polymers: C) the two associated issues with synthetic polymers are that D) synthetic polymers have two associated issues:

1.To help answer the concern about environmental pollution, b _ _ _ _ _ _ _ _ _ _ have been developed from plant materials.2. D _ _ _ _ _ _ _ _ _ plastic bowls or is the cup are designed to be thrown away after you have used it once or a few times, so they are not very good for the environment.3. Plastic can be used in everyday plastic products, which highlights that it is a v _ _ _ _ _ _ _ _ material in our everyday activities.4. With the addition of p _ _ _ _ _ _ _ _ _ _ _, plastics become softer and more flexible and it can be used in many applications.5. A _ _ is the popular choice for electronic exteriors and medical equipment its primary advantage is that it guarantees a solid shape.6. P _ _ _ _ _ _ for plastic is organic compounds added to a polymer base to give a specific color to plastics.7. Plastics can be given additional characteristics such as fire r _ _ _ _ _ _ _ _ _ to allow them to be used in aircraft.8. Thermoset plastics are stronger than thermoplastics but can not be r _ _ _ _ _ _ _ and have to be disposed of in other ways.9. Polypropyle is a strong plastic and it can usually w _ _ _ _ _ _ _ _ high temperatures, so it has a wide range of applications.10. High-Density P _ _ _ _ _ _ _ _ _ _ _ products are very safe and are not known to transmit any chemicals into foods or drinks.