R&D + GK

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CHEMICALS and Their Usages : 

C6Cl6 — Insecticide

CCl4 — Fire Exting

KNO3 — Bombs

KBr —  Photography

K2SO4 — Fertiliser

Mono Potassium Tartarate — Bakery

Phenyl - Domestic Cleaning agent

Acetone — remove nailpolish

Petrol — Dry Cleaning

Marphin — Pain Relief

Al2SO4 — Anti-fire Clothes

Pyrethrum — Mosquito 

KHMn2 — Insecticide

H2O2 — Bleaching in medicine

Li — Aeroplane manufacture & Electro-chemical Cell

Cl — Bleaching ,Water Purification

KMnO4 —  Bleaching ,Water Purification

O3 — Oxidant, save from UltraViolet rays

CaOCl2 — Bacteria killer and Bleaching

• Silver Bromide --- used in manufacture of photographic emulsions because it darkens on exposure to light.
• Silver Iodide --- Artificial rain , cloud seeding or anti-hail systems , as an antiseptic material. Due to highly photosensitive , exploited in silver-based photography.
• Lithium BiCarbonate --- used as antimanic agents, which work by decreasing abnormal activity in the brain.
• Milk of Magnesia ---  
• reduces stomach acid & increases water in the intestines which may induce defecation.  
• as a laxative to relieve occasional constipation (irregularity)
• as an antacid to relieve indigestion, sour stomach, and heartburn.

Froth Floatation Method -- Removing gangues from Sulphide Ores

NCERT Science (advanced)

Heavy water or deuterium oxide (D2O) is a form of water that contains a large amount of the hydrogen isotope deuterium which is also known as heavy hydrogen. Heavy water is used in certain types of nuclear reactors, where it acts as a neutron moderator to slow down neutrons. The different applications and uses of heavy water are: 

• Nuclear magnetic resonance.
• In Organic chemistry.
• Fourier transform spectroscopy. 
• Neutron moderator. 
• Neutrino detector.
• Metabolic rate testing in physiology and biology. 
• Tritium production.  

Heavy Water Board (HWB) is a constituent unit under Department of Atomic Energy (DAE). The organisation is primarily responsible for production of Heavy Water (D2O).

Auxin harmone in Plants : Regulation of root formation is tightly controlled by plant hormones such as auxin, and by the precise control of aspects of the cell cycle.  Such control can be particularly useful: increased auxin levels, which help to promote lateral root development, occur when young leaf primordia form and are able to synthesise the hormone.
This allows coordination of root development with leaf development, enabling a balance between carbon and nitrogen metabolism to be established.

PBDEs Polybrominated diphenyl ethers :

• PBDEs are brominated hydrocarbons in which 2-10 bromine atoms are attached to the molecular structure.
• PBDEs are used as flame retardants in a wide variety of products, including plastics, furniture, upholstery, electrical equipment, electronic devices, textiles and other household products.
• At high temperatures, PBDEs release bromine radicals that reduce both the rate of combustion and dispersion of fire.
• PBDEs exist as mixtures of distinct chemicals called congeners with unique molecular structures.
• There are three types of commercial PBDE mixtures, including pentabromodiphenyl ether (pentaBDE), octabromodiphenyl ether (octaBDE) and decabromodiphenyl ether (decaBDE). 
• DecaBDE is the most widely used PBDE globally.

Nuclear fusion:

Currently all commercial nuclear reactors are based on nuclear fission. But there is another possibility of nuclear energy generation by a safer process called nuclear fusion. Fusion means joining lighter nuclei to make a heavier nucleus, most commonly hydrogen or hydrogen isotopes to create helium, such as 2H + 2H → 3He (+ n) It releases a tremendous amount of energy, according to the Einstein equation, as the mass of the product is little less than the sum of the masses of the original individual nuclei. Such nuclear fusion reactions are the source of energy in the Sun and other stars. It takes considerable energy to force the nuclei to fuse. The conditions needed for this process are extreme – millions of degrees of temperature and millions of pascals of pressure.

The hydrogen bomb is based on thermonuclear fusion reaction. A nuclear bomb based on the fission of uranium or plutonium is placed at the core of the hydrogen bomb. This nuclear bomb is embedded in a substance which contains deuterium and lithium. When the nuclear bomb (based on fission) is detonated, the temperature of this substance is raised to 107 K in a few microseconds. The high temperature generates sufficient energy for the light nuclei to fuse and a devastating amount of energy is released.

A rainbow is a meteorological phenomenon that is caused by total internal reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. 

• It takes form of a multi-coloured circular arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun.
• The net effect of the vast array of droplets is that a circular arc of ROYGBIV from top to bottom is seen across the sky.
• Rainbows are not limited to the dispersion of light by raindrops. The splashing of water at the base of a waterfall caused a mist of water in the air that often results in the formation of rainbows. 
• A backyard water sprinkler is another common source of a rainbow. Bright sunlight, suspended droplets of water and the proper angle of sighting are the three necessary components for viewing one of nature’s most splendid masterpieces.

Gas hydrates :

• are formed when a gas such as methane gets trapped in well-defined cages of water molecules forming crystalline solids. 
• In terrestrial conditions, gas hydrates are formed naturally under the sea bed and glaciers under high pressure, low temperature conditions. 
• Methane hydrate is a potential source of natural gas.
• Gas hydrates are found in equilibrium under conditions of high pressures and low temperatures. These conditions are found onshore under permafrost in the polar regions and offshore along the continental shelf margins.

IIT Madras – The methane and CO2 hydrates were produced in the lab at very low pressures (ten thousand billionth of atmospheric pressure) and temperature (as low as -263 degree C) to simulate the conditions of deep space.

Photosynthetically Active Radiation (PAR) 

• is the amount of light available for photosynthesis, which is light in the 400 to 700 nanometer wavelength range. 
• PAR changes seasonally and varies depending on the latitude and time of day. 
• Levels are greatest during the summer at mid-day. 
• Air pollution also affects PAR by filtering out the amount of sunlight that can reach plants. 
• Photosynthetically Active Radiation is needed for photosynthesis and plant growth. 
• Higher PAR promotes plant growth. 

Commensalism is a type of symbiotic relationship between organisms in which one organism benefits without harming the other in any way.

Other types of symbiotic relationships include mutualism, in which both the organisms involved benefit from each other, and parasitism, where one of the organisms is benefited, while the other is harmed.

Many birds form a commensal relationship with some species of ants like the army ants. A great number of army ants trail on the forest floor, and while moving, stir up many insects lying in their path. The birds follow these army ants and eat up the insects that try to escape from them. The birds benefit by catching their prey easily, while the army ants are totally unaffected.

CLOUD SEEDING :

It uses below chemicals

• Calcium carbide        Ca2C
• Sodium Chloride        NaCl
• Dry ice                         CO2
• Liquid propane           C4H10

CO2 in the form of dry ice is also important in the making of artificial rain. This chemical is a colourless gas with chemical compound CO2. While carbon monoxide is carbon atom that bonds only with one oxygen atom, carbon dioxide bonds with two atoms and is not as dangerous as monoxide one. When it is in the form of ice, carbon dioxide will help to weigh down the clouds and press the trapped water to fall down to surface of the earth. Dry ice is not similar to ordinary ice so it functions purely as additional weight to the cloud and does not contain water.

Propane is an alkane compound with three carbon atoms. It has the chemical formula of C3H8. Propane is a common substance used as fuel is a natural gas that often is colorless but under certain circumstance can turn into liquid form. Propane gas as cloud seeding material acts as a pusher to encourage the clouds to precipitate. The liquid form of it will also trigger the clouds to release a liquid form of itself, further cause rain. Propane needs other chemical to be able to properly run its function in cloud seeding. Regardless, propane is important in the process of artificial rain.

During agitation state calcium carbide is used in the making of artificial rain. Calcium carbide along with calcium oxide acts as absorbers of water vapour. It consists of salt and urea or ammonium nitrate. This chemical is a calcium compound with formula CAC2. It is usually colorless but can also appear whitish. To produce calcium carbide, lime and coke mixture in an electric arc furnace reaction will result in calcium carbide. Furthermore, the role in artificial rain is to trigger precipitation in the sky clouds.

Alternative chemical beside silver iodide to create artificial rain is sodium chloride. Sodium chloride is a chemical compound with formula NaCl. The formation of sodium chloride is one portion of sodium and one portion of chloride. Commonly known as salt, it is an ionic compound that can also acts as denser in artificial rain making. The chemical will make the cloud dense with big beads of water, further pushing them to create precipitation and drop rain onto the earth’s surface. The use of it is considered to be more expensive compared to silver iodide and is only used occasionally during extreme dry season.

X-Rays :

• X-ray microscopy to acquire high resolution images, and in X-ray crystallography to determine the positions of atoms in crystals. 
• A very high radiation dose over a short period of time causes radiation sickness, while lower doses can give an increased risk of radiation-induced cancer. 
• X-rays interact with matter in 3 main ways, through photo-absorption, Compton scattering and Rayleigh scattering.  The strength of these interactions depends on the energy of the X-rays and the elemental composition of the material.

PLANKTON in Temperate high Latitudes :

• Highest concentration of plankton is found at higher latitudes while tropics and subtropics have lower concentrations. 
• It is due to nutrient limitation brought about by strong, year-round thermocline (temperature gradients) and pycnocline (salinity gradients). 
• Pycnocline refers to the rapid change in density with depth, and thermocline, a rapid change in temperature with depth. 
• Both of these limit circulation of nutrients to the surface where planktons grow. 
• However, in areas where ocean upwelling occurs, nutrients are cycled to the surface and rich plankton grounds can be found. 

Ultraviolet (UV) : 

• is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.
• it is present in sunlight constituting about 10% of the total light output of the Sun.
• UV radiation of sunlight after reaction produces Ozone(O3).
• Ozone plays a key role in the temperature structure of the Earth’s atmosphere. Without the filtering action of the ozone layer, more of the Sun’s UV-B radiation would penetrate the atmosphere and would reach the Earth’s surface.

Father of Human Geography : Fedrick Retgel , Germany 1904

After CFC , next ozone destroyer : NO2 

Weathering : Geological process


Rennet : 

• a complex set of enzymes produced in the stomachs of ruminant mammals. 
• Chymosin, its key component, is a protease enzyme that curdles the casein in milk. This helps young mammals digest their mothers' milk. 
• Rennet can also be used to separate milk into solid curds for cheesemaking and liquid whey. 
• In addition to chymosin, rennet contains other important enzymes such as pepsin and a lipase. 
• Rennet is used in the production of most cheeses. The mammal's digestive system must be accessed to obtain its rennet.  

Plasmids :  

• is a small, circular, double-stranded DNA molecule that is distinct from a cell's chromosomal DNA. 
• Plasmids naturally exist in bacterial cells, and they also occur in some eukaryotes and archaea. 
• Often, the genes carried in plasmids provide bacteria with genetic advantages, such as antibiotic resistance.

X-rays : Wilhelm Conrad Röntgen produced and detected electromagnetic radiation in a wavelength range known as X-rays or Röntgen rays, an achievement that earned him the first Nobel Prize in Physics in 1901. 

Methane Emission : 

• It is 20 times effective in global warming in form of Green house gas compare to CO2.
• The main source in India from where it gets emitted are Livestock , Paddy Fields, Termites.
• In paddy fields, the water blocks oxygen from penetrating the soil, creating ideal conditions for bacteria that emit methane. The longer the flooding lasts, the more those bacteria build up.
• When rice is grown with no oxygen, the soil organic matter decomposes under anaerobic conditions and produces methane that escapes into the atmosphere.
• Terrestrial arthropod-like termite (दीमक - एक प्रकार का घरेलू कीट )  contributes to the methane emission resulting from their digestive system. 
• Termites have developed a symbiotic relationship with colonies of bacteria that can break complex molecular structure of organic compounds like cellulose to form energy and methane as a byproduct.

METHANOL :

• Methanol can be used as an energy producing fuel, transportation fuel and cooking fuel, cutting down India’s oil import bill by an estimated 20% over the next few years.
• Unlike CNG, using methanol as a transportation fuel would require minimal alteration in the vehicles.
• Methanol is a clean-burning fuel that produces fewer smog-causing emissions — such as sulphur oxides (SOx), nitrogen oxides (NOx) and particulate matter — and can improve air quality and related human health issues.

Electromagnetic Waves : physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes theelectromagnetic interaction.

CGXUVIMR

                               ---------------------> Increasing Wavelength
COSMIC > GAMMA > XRAY > ULTRAVIOLET > VISIBLE > INFRARED > MICROWAVE  > RADIO
                               Increasing Frequency , Energy  <------------------------



Energy E = hv

More Frequency More Energy and Less wavelength --- presents in UV , X-Ray , Gamma rays

Less Frequency Less Energy and More wavelength --- presents in IR , Microwave , Radio rays



JV Narlikar


Optical Fibre : In 1952, UK based physicist Narinder Singh Kapany invented the first actual fiber optical cable based on John Tyndall's experiments three decades earlier.  It works on principle of TIR Total Internal Reflection.


JET Streams :

• Jet streams are currents of air high above the Earth. They move eastward at altitudes of about 8 to 15 kilometers (5 to 9 miles). They form where large temperature differences exist in the atmosphere. Tropopause is one such spot.
• Jet streams are so fast and powerful that airplanes have difficulty flying against them. Pilots either fly with the jet stream or above it; they do not attempt to fly against it.
• An air current is a flowing movement of air within a larger body of air. 
• Air currents flow in the atmosphere, the layers of air surrounding the Earth. They form because the sun heats the Earth unevenly. 
• As the sun beams down on the Earth, it warms some areas, particularly the tropics, more than others, such as the poles. 
• As the Earth is heated, it warms the air just above it. The warmed air expands and becomes lighter than the surrounding air. It rises, creating a warm air current. 
• Cooler, heavier air then pushes in to replace the warm air, forming a cool air current. Jet streams are air currents in the highest part of the atmosphere.