General Science Chemistry MCQs

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Oxalic acid is an organic compound with the formula C₂H₂O₄. Some call it “crab acid” due to its appearance. Its condensed formula is HOOCCOOH, reflecting its classification as the simplest dicarboxylic acid.

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Magnetite is the finest iron ore with a very high content of iron up to 70 per cent. It has excellent magnetic qualities, especially valuable in the electrical industry.
Hematite ore is the most important industrial iron ore in terms of the quantity used, but has a slightly lower iron content than magnetite. (50-60 per cent)

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The Kimberley Process (KP) is a commitment to remove conflict diamonds from the global supply chain. India was one of the founder participants in the Kimberley Process Certification Scheme (KPCS). Launched in 2003, the Kimberley Process is a coalition of governments, civil society and the diamond industry to eliminate the trade in so-called conflict diamonds.

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The Scoville scale is a measure of the ‘hotness’ of a chili pepper or anything derived from chili peppers, i.e. hot sauce. The scale is actually a measure of the concentration of the chemical compound capsaicin which is the active component that produces the heat sensation for humans.

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Chlorargyrite is the mineral form of silver chloride (AgCl). It is also known as cerargyrite and, when weathered by desert air, as horn silver. Silver chloride is formed by the disappearance of the initial silver oxide layer.

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he first human-made plastic was made by Alexander Parkes in 1855, when he synthesized celluloid. The new discovery found its use in photographic films, but it could not be used for making containers or insulators for electric circuits.
The first true plastic was made in 1909 by Leo Baekeland, who synthesized Bakelite. The hard plastic could be used to make handles, auto parts, etc. The First World War witnessed improvements in the manufacture of polystyrene and polyvinyl chloride, which found use in plumbing equipment and electric wire insulation. Nylon was synthesized in the 1930s. By 1950, plastics became quite popular and as a result we can see them everywhere today

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In dry cleaning, cleansing is achieved by the action of a solvent, which dissolves out the sticky matter due to its like nature. Dry cleaning fluids serve as a vehicle to carry away the soil. Camphene, naphtha, benzene, benzol, petrol, carbon tetrachloride, trichloroethylene and tetrachloroethylene are some of the frequently used dry cleaning fluids. However, tetrachloroethylene (perchloroethylene), abbreviated “perc” in the industry is a common solvent used in Dry Cleaning.

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Recently, the International Union of Pure and Applied Chemistry (IUPAC) have officially confirmed the permanent addition of four new elements to the periodic table. The IUPAC had announced last week that all four elements with atomic number 113, 115, 117 and 118 have met the criteria for discovery.Thus; it completed the seventh row of periodic table.

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The oil which contains sulphur amount less than 0.5% is called Sweet Crude Oil. If the Sulphur content is more than 0.5%, it will be called Sour Crude Oil. The Brent crude oil is having around 0.37% Sulphur and that is why Brent Crude Oil is a Sweet crude Oil. Sweet Crude Oil is of High quality, low sulphur crude oil used for processing of gasoline. The more amount of Sulphur in sour crude makes it toxic, and production of Gasoline is more expensive in case of sour crude. The word “sweet” since a gently sweet taste and pleasing aroma due to the little level of Sulfur gives the oil with. The Brent Crude Oil is a sweet crude oil mainly produced in North Sea. It is largest of the several key classifications of crude oil comprising of Ekofisk, Brent Crude, Forties, Brent Sweet Light Crude and Oseberg. Its manufacturer also known as London Brent, Brent petroleum and Brent Blend.

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Silica gel is used in a transformer for the absorption of moisture from air during breathing out of the transformer. If the relative water moisture content is increased, then this leads to the decrease of the dielectric strength of mineral oil. The result is that the breakdown voltage drastically reduced in the range of 20-50% of relative water content.