UKPCS Science Chemistry: Polyethylene #28

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

Polyethylene (abbreviated PE) or polyethene is the most common plastic. The annual global production is around 80 million tonnes. Its primary use is in packaging (plastic bags, plastic films, geomembranes, containers including bottles, etc.). Many kinds of polyethylene are known, with most having the chemical formula (C2H4)n. PE is usually a mixture of similar polymers of ethylene with various values of n.

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UKPCS Science Chemistry: Nylon & Rayon #27

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

Nylon is a generic designation for a family of synthetic polymers, more specifically aliphatic or semi-aromatic polyamides. They can be melt-processed into fibers, films or shapes. Nylon is made from polyamide fiber, derived from a diamine and a dicarboxylic acid that is formed into thin strands and woven into fabric. It is a synthetic fabric that utilizes the chemical by-products of coal, petroleum and agricultural products. Continue reading “UKPCS Science Chemistry: Nylon & Rayon #27”

UKPCS Science Chemistry: POLYMER #26

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

POLYMER

A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Because of their broad range of properties, both synthetic and natural polymers play an essential and ubiquitous role in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, visco-elasticity, and a tendency to form glasses and semi-crystalline structures rather than crystals. Continue reading “UKPCS Science Chemistry: POLYMER #26”

UKPCS Science Chemistry: Ethanol #25

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

ETHANOL

Ethanol, also called alcohol, ethyl alcohol, and drinking alcohol, is the principal type of alcohol found in alcoholic beverages. It is a volatile, flammable, colorless liquid with a slight characteristic odor. Its chemical formula is C2H5-OH (an ethyl group linked to a hydroxyl group), and is often abbreviated as EtOH. Continue reading “UKPCS Science Chemistry: Ethanol #25”

UKPCS Science Chemistry: Alcohol-methanol #25

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

ALCOHOL

In chemistry, an alcohol is any organic compound in which the hydroxyl functional group (–OH) is bound to a saturated carbon atom. The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), the predominant alcohol in alcoholic beverages. An important class of alcohols, of which methanol and ethanol are the simplest members is the saturated straight chain alcohols, the general formula for which is CnH2n+1OH. Continue reading “UKPCS Science Chemistry: Alcohol-methanol #25”

UKPCS Science Chemistry: Petroleum product and there uses# 24

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

Petroleum product and there uses:

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UKPCS Science Chemistry: Varnish:# 23

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

Varnish

Varnish is a transparent, hard, protective finish or film that is primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish has little or no color, is transparent, and has no added pigment, as opposed to paints or wood stains, which contain pigment and generally range from opaque to translucent. Varnishes are also applied over wood stains as a final step to achieve a film for gloss and protection. Continue reading “UKPCS Science Chemistry: Varnish:# 23”

UKPCS Science Chemistry: EXPLOSIVES:# 22

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

EXPLOSIVE

Explosive, is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure.

The potential energy stored in an explosive material may, for example, be

  • chemical energy, such as nitroglycerin or grain dust
  • pressurized gas, such as a gas cylinder or aerosol can
  • nuclear energy, such as in the fissile isotopes uranium-235 and plutonium-239

In contrast, some materials are merely combustible or flammable if they burn without exploding. The distinction, however, is not razor-sharp. Certain materials—dusts, powders, gasses, or volatile organic liquids—may be simply combustible or flammable under ordinary conditions, but become explosive in specific situations or forms, such as dispersed airborne clouds, or confinement or sudden release.

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UKPCS Science Chemistry: DETERGENTS:# 21

Oracle IAS, the best coaching institute for UPSC/IAS/PCS preparation in Dehradun brings to you UKPCS Science Chemistry (paper 6). 

DETERGENTS:

Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.

A detergent is an effective cleaning product because it contains one or more surfactants. Because of their chemical makeup, the surfactants used in detergents can be engineered to perform well under a variety of conditions. Such surfactants are less sensitive than soap to the hardness minerals in water and most will not form a film. Continue reading “UKPCS Science Chemistry: DETERGENTS:# 21”