Question

13. Rayon is a fiber regenerated from
14.
is often used are substitute for wool.
15.
16.
17.
is used as a coating on the surface of non-stick frying pans.
synthetic fiber is commonly used to make strong ropes.
are long-chain polymers made by linking of several ester units.
plastics are set into a particular shape cannot be remolded.
is the most common source for synthetic fibers.
18.
19.
20.
and
are the metals which do not react with air.
in nature.
21. Oxides of non-metals are usually
purposes.
22. Tincture iodine is used in

Answer 1

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