Class 12th Biology 2012 Set3 Delhi Board Paper Solution
Question 25
(a) Why are the colourful polysterene and plastic packagings used for protecting the food, considered an environmental menace?
(a) Why are the colourful polysterene and plastic packagings used for protecting the food, considered an environmental menace?
(b) Write about the remedy found for the efficient use of plastic waste by Ahmed Khan of Bangalore.
Answer
(a) Colourful polysterene and plastic packaging used for protecting the food are considered to be environmental menace as plastic is non-biodegradable and its recycling process is very costly and includes manual participation thus exposing workers to toxic substances produced during recycling process.
(b) The remedy found for efficient use of plastic waste by Ahmed Khan of Bangalore was making of Polyblend, a fine powder of recycled modified plastic. This mixture
is mixed with the bitumen, and is used to lay roads.In collaboration with R.V. College of Engineering and Banglore city Corporation, Ahmed Khan proved that blends of Polyblend and Bitumen, when used to lay roads enhanced the bitumen’s water repellant properties and helped to increase road life by a factor of three.
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