Chemistry Miscellaneous (Elements, Compounds and Processes) - III

More reactive metals have a greater tendency to lose electrons and form positive ions.

Reactivity: Potassium > Sodium > Lithium > Barium > Strontium > Calcium > Magnesium > Aluminum > Manganese .. > Iron .. > Copper .. > Silver > Gold > Platinum

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The hardest pure element is carbon in the form of a diamond.

Hardness Metal: Tungsten > Chromium > Titanium > Gadolinium > Iron

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The heaviest element that occurs in large quantity is uranium (atomic number 92).

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A pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) in minute crystalline form, which has deposited in concentric layers.

"Sapphire" and "ruby" are varieties of Aluminium oxide(Al₂O₃).

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Sodium-vapour lamps are good for night-time illumination because of their high efficiency and because the light they produce penetrates mist and fog particularly well.

A fluorescent lamp tube is filled with a gas containing low pressure mercury vapour and noble gases at a total pressure of about 0.3% of the atmospheric pressure.

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Monazite is an important ore for thorium, lanthanum, and cerium.

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Soldering is a process used for joining metal parts to form a mechanical or electrical bond.

Solder is a metal alloy usually made of tin and lead which is melted using a hot iron.

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German silver is an alloy of zinc, copper, and nickel metals. The percentage of silver in German silver is zero.

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Anthracite is the highest ranked coal with the carbon percentage of above 87%.

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Gaseous cycles are a type of biogeochemical cycle in which the reservoir is the air or the oceans (via evaporation).

Such cycles include those of Nitrogen (N), Oxygen (O), Carbon (C), and Water.

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Deep sea divers normally breathe a mixture of nitrogen and oxygen, called nitrox.

But in some cases instead of nitrox, divers use heliox - a mix of helium and oxygen - or trimix, which combines all three gases.

Excess oxygen causes oxygen toxicity at a higher pressure than 6 metres underwater, therefore, deep-sea divers use a mixture of gases and not just oxygen.

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A gas balloon is a balloon that rises and floats in the air because it is filled with a gas lighter than air (such as helium or hydrogen). Helium is an inert gas that will not burn or explode so is much safer to use in balloons instead of hydrogen.

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Bordeaux mixture a combination of copper sulfate and calcium hydroxide in water - is an effective fungicide and bactericide that has been used for decades to control diseases of fruit and nut trees, vine fruits, and ornamental plants.

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Nitrogen, unlike air, does not permeate easily through rubber or seals found in aircraft components.

It is also inert and therefore ideal to inflate aircraft tyre to prevent oxidative degradation of the rubber, with the added advantage of its inert nature preventing fire due to brake heat transfer.

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The foul smell of dead fish is due to the compound Amino compounds.

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Typically, chlorine is added to disinfect the water to kill any remaining bacteria and microorganisms.

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Water is a good solvent of ionic salts because it has a high dipole moment. Salts are ionic compounds which, when dissolved in water, break up completely into ions.

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Desalination is the process of removing salts or other minerals and contaminants from seawater, brackish water, and wastewater effluent and it is an increasingly common solution to obtain fresh water for human consumption and for domestic/industrial utilization.

Pure water can be obtained from the sea by the process of Reverse osmosis.

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Carbon black is produced during the furnace process mostly by burning natural gas, which has methane as a predominant compound.

This carbon black can be used in various industries such as printing inks.

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The Bhopal disaster occurred when about 45 tons of the gas methyl isocyanate escaped from a plant owned by a subsidiary of the U.S.-based Union Carbide Corporation.

Methyl isocyanate is a colorless highly flammable liquid that evaporates quickly when exposed to the air.

Methyl isocyanate is used to produce carbamate pesticides.

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The most commonly used chemical in fruit ripening is called ethephon (2-chloro-ethyl-phosphonic acid).

It penetrates into the fruit and decomposes ethylene (promotes riping).

Another chemical that is regularly used is calcium carbide, which produces acetylene, which is an analogue of ethylene.

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Gases used in welding are Oxygen and acetylene.

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Examples of naturally occurring polymers are: silk, wool, leather, DNA, starch, cotton, cellulose and proteins.

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Octane Number - Petrol, Cetane Number - Diesal

The fuel used in a Diesal engine is - Vapour of Diesal & Air

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An antiknock agent is a gasoline additive used to reduce engine knocking and increase the fuel's octane rating by raising the temperature and pressure at which auto-ignition occurs.

Tetraethyl lead (TEL) is used as an antiknock agent in gasoline and jet fuels.

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Charcoal used to decolourise raw sugar is - Animal Charcoal

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Aspirin, also known as acetylsalicylic acid, is a medication used to reduce pain, fever, or inflammation.

Aspirin is prepared by chemical synthesis from salicylic acid through acetylation with acetic anhydride.

Aspirin have excellent and essentially similar antipyretic (used to prevent or reduce fever) activity.

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An emulsion is a mixture of two or more liquids that are normally immiscible owing to liquid-liquid phase separation.

Familiar foods illustrate examples: milk is an oil in water emulsion; margarine is a water in oil emulsion; and ice cream is an oil and air in water emulsion.

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A colloid is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance.

Some examples include milk, butter, blood, honey etc.

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Milk tastes sour when kept in the open for sometime due to - lactic acid.

Fermentation converts the lactose to lactic acid, which has a sour flavor.

A bacteria called Lactobacillus is used in making curds which provides suitable acidic environment to coagulate the casein (milk protein) forming curds.

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Eugenol, also called clove oil, is an aromatic oil extracted from cloves that is used widely as a flavoring for foods.

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Vegetable oil is used in soap making - Soybean oil, like canola, safflower, and sunflower.

Soap removes grease by the process of Emulsification.

Emulsification is the process of dispersing two or more immiscible liquids together to form a semistable mixture.

Soaps are made from natural ingredients, such as plant oils (coconut, vegetable, palm, pine) or acids derived from animal fat.

Detergents, on the other hand, are synthetic, man-made derivatives.

Detergent is a refining agent.

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Urea is a common source of nitrogen, it contains 46% elemental nitrogen (N)

Urea, however, contains nitrogen in amide form but this form of nitrogen is swiftly converted by soil micro-organisms into ammonical form and then into nitrate form (used by plants).

Urea is now prepared commercially in vast amounts from liquid ammonia and liquid carbon dioxide.

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DAP (Diammonium phosphate) is the most popular phosphatic fertiliser because of its high nutrient content and good physical properties.

The composition of DAP is 18% Nitrogen and 46% Phosphorus pentoxide (P₂O₅).

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A "foliar application" means that you are feeding plants by applying liquid fertilizer directly to the leaves as opposed to in the soil.

Urea is the most popular fertilizer for foliar application.

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Sunn hemp is a multipurpose tropical and subtropical legume grown in many countries, notably India, mainly for green manure.

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Allethrin is a synthetic household insecticide that kills flies, mosquitoes, garden insects, etc.

Pyrethrum has been used for centuries as an insect (mosquito) repellent.

Pyrethrum is made from the flowers of the Chrysanthemum plant (a seed plant).

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Potassium Cyanide or "Zinc phosphide" or "Aluminium phosphide" has been used to extract metals from ore and as a rat poison (rodenticide).

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The age of rocks is determined by radioactive dating.

The age of the fossils is determined by the Radioactive carbon dating (⁶C¹⁴: Carbon 14) technique.

The age of earth is determined by uranium dating.

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Crooked Glass can cut off the UV rays.

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A pungent smell often present near the urinals is due to ammonia.

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Titanium is called the metal of the future.

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Magnesium burns a very bright white, so it is used to add white sparks or improve the overall brilliance of a firework.

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Material used in dry washing: Petrol, Alcohol, Benzene etc.

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Red ink is prepared from - Eosin and yellow from Sodium chromate.

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Acetone ((CH₃)₂CO) is a liquid solvent that can break down and dissolve other substances.

Companies include acetone in products such as nail polish remover, paint remover, and varnish remover.

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A standard dry cell comprises a zinc anode, usually in the form of a cylindrical pot, with a carbon cathode in the form of a central rod.

The electrolyte is "ammonium chloride" and "zinc chloride" in the form of a paste next to the zinc anode.

"Manganese Dioxide (MnO2)" is primarily used as a part of dry cell batteries.

A dry cell cannot be recharged.

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Monosodium glutamate (MSG) is a sodium salt of glutamic acid.

Monosodium glutamate (MSG) is found naturally in chinese fast food and some foods including tomatoes and cheese in this glutamic acid form.

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Phenyl is a phenol derivative possessing effective germicidal properties.

Phenol is used (in low concentrations) as a disinfectant in household cleaners and in mouthwash.

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Bisphenol A is a chemical compound primarily used in the manufacture of various plastics (food packaging material).

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The head of safety matches are made of an oxidizing agent such as potassium chlorate, mixed with sulfur, fillers and glass powder.

The side of the box contains red phosphorus, binder and powdered glass.

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White phosphorous is an element which reacts with atmospheric oxygen and forms fumes like substance and glows in dark.

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Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds (VOCs) react to sunlight, creating a brown haze above cities.

It tends to occur more often in summer, because that is when we have the most sunlight.

Ozone is the principal component of air pollution of this kind.

Read Also: Chemistry Miscellaneous (Elements, Compounds and Processes) - I

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