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

Explanation

(i) From the given passage, we can conclude that the students show awareness about the enviromnent.
(ii) A polymer that can be decomposed by microorganisms within a definite period of time, so thet the polymer or its deraded product does not cause any harm to the environment, is called a bio-degradable polymer. For example, poly - `beta` - hydroxybutyrate - Co - `beta` - hydroxy valerate (PHBV) is a bio-degradable aliphatic polyester.
`[{:(-CH_(2) -CH_(2)-C-O-CH-CH_(2)-CH-C-),(" "|" "||" "|" "||),(" "CH_3" "O" "CH_2-CH_3),(" "PHBV):}]_(n)`
(iii) Polythene is an addtion polymer that is formed by addition of ethene molecules.
`underset("Polythene Polymer")underset("Ethane")(nCH_2=CH_2)overset("polim erisation")tounderset("Re peating unit")(n[-CH_2-CH_2-])to[CH_2-CH_2]_n`