Tag: chemistry
Questions Related to chemistry
Synthetic fibers are made by :
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condensation
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hydrolysis
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polymerization
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none of above
Synthetic fabrics are textiles made from man-made rather than natural fibers. Synthetic (chemically produced) fibres are made by joining monomers into polymers, through a process called polymerization. A synthetic fibre, when magnified, looks like plastic spun together. Polymerization is the formation of macromolecules through repetition of basic units. Initially, the various components are solids and first must be converted to a liquid state to be extruded into fibers. The materials are chemically converted, dissolved, or melted, turning into a thick liquid.
Which of the following is a disadvantage of synthetic fibre?
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melt before burning
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repel moisture
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clothes are garishly lustrous
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All of the above
Clothes made of pure synthetic fibres are garishly lustrous. Synthetic fibres melt before burning. So clothes made of such fibres stick to the skin when in contact with a flame, causing burns. Therefore, they should not be worn in the kitchen or while setting off fireworks.
Cellulose dissolved in a mixture of sodium hydroxide (NaOH) and carbon disulphide produces :
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Viscose
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Rayon
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Polyamide
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Polyester
Cellulose (say, cotton) is dissolved in a mixture of sodium hydroxide (NaOH) and carbon disulphide ($CS _2$, a solvent). A viscous liquid (i.e., a liquid which cannot flow freely) called viscose is obtained. The viscose is then forced through spinnerets (which have small holes) into an acid bath, and filaments of viscose rayon are obtained.
To which of the following does the $4$R principle apply the most?
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Synthetic fibre
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Natural fibre
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Metals
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Plastic
Plastic follow all the 4R principles: Reduce, reuse, recycle, restore.
Artificial fibres is the other name given to ____________.
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plastic
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synthetic fibres
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plant fibres
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animal fibres
Artificial fibres is other name given to synthetic fibres. Examples of synthetic fibres are nylon, PVC, polyester, etc.
The first synthetic thermosetting plastics is :
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bakelite
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mellamine
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nylone
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PVC
Bakelite is the first synthetic thermosetting plastics.
This is the synthetic fibre :
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Wool
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Cotton
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Acrylic
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Polystyrene
Acrylic is a man-made fiber it resembles wool and hence it is also known as artificial wool or synthetic wool. In commercial use acrylic is cheaper than natural wool and can be dyed in various colours.
These are the synthetic materials which we come across in our daily life :
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plastic
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glass
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cement
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wool
Synthetic materials in daily life are:
Commonly used synthetic fabrics are:
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polyester
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nylon
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rayon
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acrylic
Fabric | raw material |
---|---|
Polyester | ester |
Nylon | carpolactam |
Rayon | wood pulp |
Acrylic | polyacryonitrile |
The fabrics that are produced entirely from chemicals are known as synthetic fabrics. Examples of synthetic fabrics are nylon, polyester, rayon, and acrylic
Synthetic fibres are made using __________ as raw materials.
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woollen products
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polymers
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cotton
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petrochemicals
Synthetic fibres are not obtained from natural resource but it is manufactured in a laboratory using petrochemicals. Synthetic fabrics are textiles made from man-made rather than natural fibres. Examples of synthetic fabrics include polyester, acrylic, nylon, rayon, acetate, spandex, latex, Orlon and kevlar. Synthetic (chemically produced) fabrics are made by joining monomers into polymers, through a process called polymerisation.