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- Question 1 of 50
Catalytic converters are generally made from:
A catalytic converter is a device used in motor vehicles to reduce the damage caused to the environment by poisonous gases. Catalytic converters are generally made from transition metals. Transition metals such as platinum (Pt), palladium (Pd), and rhodium (Rh) are used in the catalytic converters.
- Question 2 of 50
The soft silvery metallic element which ionizes easily when heated or exposed to light and is present in atomic clocks is:
Caesium is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal. Caesium ionizes easily when heated or exposed to light because it is strongly photoelectric (easily loses electrons when struck by light). Cesium 133 is the element most commonly chosen for atomic clocks.
- Question 3 of 50
The mercury and sodium street lamps light up because of:
The mercury and sodium street lamps light up because of atomic emission. An electric discharge takes place when electricity is passed through sodium vapors at low or high pressure. As a result, the valence electron present in sodium atoms becomes excited and emits light. The mercury vapor lamp works by creating an electric current to mercury vapor within a sealed glass jacket.
- Question 4 of 50
The green colour seen in firework displays is due to the chloride salt of:
Metals are used in crackers like strontium carbonate is used for red fireworks, calcium carbonate is used for orange fireworks, sodium nitrate is used for Yellow fireworks, barium Chloride is used for green fireworks and copper chloride is used for blue Firework.
- Question 5 of 50
The most commonly used bleaching agent is:
The most commonly used bleaching agent is chlorine. Chlorine can act as a bleaching agent due to the nascent oxygen it can produce in the reaction with water. Basically, one Cl atom gets oxidised and the other gets reduced when chlorine gas reacts with water.
- Question 6 of 50
Peroxyacetyl nitrate is a:
Peroxyacetyl nitrate is a secondary pollutant present in photochemical smog. It is thermally unstable and decomposes into peroxyethanoyl radicals and nitrogen dioxide gas. It is a lachrymatory substance, meaning that it irritates the lungs and eyes.
- Question 7 of 50
Hydrogen peroxide is an effective sterilizing agent. Which one of the following products results when it readily loses active oxygen?
Hydrogen peroxide (H2O2) is water (H2O) with an extra oxygen molecule. H2O2 contains a single oxygen-oxygen bond. When its oxygen-oxygen bond breaks, hydrogen peroxide decomposes into water and oxygen.
- Question 8 of 50
What happens when a drop of glycerol is added to crushed KMnO4 spread on a paper?
When a drop of glycerol is added to crushed KMnO4 spread on a paper, the paper will ignite. As the glycerin comes in contact with the KMnO4, the oxidizing properties of the permanganate ion come into play with the glycerin. The oxidation of the glycerin is very exothermic and after a few seconds, the released heat causes the glycerin to also ignite and burst into flame.
- Question 9 of 50
Which of the following can be found as pollutants in the drinking water in some parts of India?
1. Arsenic, 2. Sorbitol, 3. Fluoride, 4. Formaldehyde, 5. Uranium
Select the correct answer using the code given below:
Arsenic, mercury, cadmium and fluoride are the main pollutants in the drinking water which are found in some parts of India.
- Question 10 of 50
Photochemical smog is a resultant of the reaction among:
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. The major chemical pollutants in Photochemical smog are NO and NO2, VOCs, Ozone (O3) and PAN (Peroxyacetyl Nitrate).
- Question 11 of 50
When a helium atom loses an electron it becomes:
When a helium atom loses an electron it becomes a positive helium ion. When an atom gains/loses an electron, the atom becomes charged, and is called an ion. If a neutral atom gains an electron, it becomes negative. This kind of ion is called an anion. If a neutral atom loses an electron, it becomes positive. This kind of ion is called a cation.
- Question 12 of 50
Heavy metals got their name because compared to other atoms they have:
Heavy metals are generally referred to the metals with relatively high atomic weights in the range of 63.5–200.6 g mol−1 and densities more than 5gcm−3.
- Question 13 of 50
The purest form of iron is:
Most iron is found in minerals formed by the combination of iron with other elements. The purest form of iron is Wrought iron. It contain 99.5% iron, 0.25% carbon and 0.25% other impurities.
- Question 14 of 50
Combustion is a:
Combustion is a chemical process. It is a chemical reaction between substances, usually including oxygen and usually accompanied by the generation of heat and light in the form of flame.
- Question 15 of 50
Which of the following is not a form of carbon?
Soot, Graphite and Charcoal are different forms of carbon particles. Hematite is not a form of carbon, it is an ore of iron.
- Question 16 of 50
Natural radioactivity was discovered by:
Natural radioactivity was discovered by Antoine Henri Becquerel. Henri Becquerel (1852-1908) was a French physicist who discovered radioactivity through his investigations of uranium and other substances. In 1903 he shared the Nobel Prize for Physics with Pierre and Marie Curie.
- Question 17 of 50
Which of the following is used in pencils?
Graphite is used in pencil lead because it is soft and leaves an impression on the paper and cleans easily between the layers. It has layered structure layers are held by van der Waal forces.
- Question 18 of 50
The rusting of metal iron in the air needs both:
Rusting is an oxidation reaction. The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust. Hence, iron rust when they come into contact with water and oxygen – both are needed for rusting to occur.
- Question 19 of 50
Acid rain is caused by:
Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide (SO2) and nitrogen oxides (NOx) are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain. Nitrogen oxide (NO) and nitrogen dioxide (NO2) are collectively known as nitrogen oxides (NOx).
- Question 20 of 50
The process of improving the quality of rubber by heating it with sulphur is called:
The process of improving the quality of rubber by heating it with sulphur is called Vulcanization. It is the process of converting natural rubber to more strong and more elastic form.
- Question 21 of 50
The pollutant responsible for ozone holes is:
Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and halons destroy the earth’s protective ozone layer, which shields the earth from harmful ultraviolet rays generated from the sun. CFCs and HCFCs also warm the lower atmosphere of the earth, changing global climate.
- Question 22 of 50
The alkaloid naturally found in coffee, cocoa and cola nut is:
Caffeine is an alkaloid (naturally occurring organic compound) in the xanthine family. It is a drug that stimulates (increases the activity of) the brain and nervous system. Caffeine is found in many drinks such as coffee, cocoa, cola nut, soft drinks and energy drinks.
- Question 23 of 50
Which of the following is not a noble gas?
Noble gas (also called inert gases) is any of the seven chemical elements that exhibit great stability and extremely low reaction rates. The elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og). Hydrogen is not a noble gas.
- Question 24 of 50
Kelps are large brown algae seaweeds that make up the order Laminariales. It grows in shallow saltwater near coastal areas around the world. It is a rich source of iodine, minerals, antioxidants, fiber, proteins, and healthy carbohydrates.
- Question 25 of 50
Ink is prepared from:
Historically, tannins extracted from oak galls were used for making ink by mixing them with iron compounds, such as iron(II) sulfate to form complex, water-soluble blue-black compounds.
- Question 26 of 50
Formic acid is produced by:
Formic acid (methanoic acid) is produced by red ants. It is an important intermediate in chemical synthesis and occurs naturally, most notably in red ants.
- Question 27 of 50
Chemical decomposition of an organic compound by water is called as:
Hydrolysis is a double decomposition reaction with water as one of the reactants. It is any chemical reaction in which a molecule of water breaks one or more chemical bonds.
- Question 28 of 50
Which of the following is not a nitrogenous fertilizer?
Superphosphate is not a nitrogenous fertilizer. The nitrogenous fertilizer industry includes the production of synthetic ammonia, nitric acid, ammonium nitrate, ammonium sulphate and urea.
- Question 29 of 50
CaC2 on treatment with water gives:
Calcium carbide (CaC2) reacts with water to give acetylene (IUPAC name ethyne) gas and calcium hydroxide.
- Question 30 of 50
The percentage of nitrogen present in ammonium sulphate is:
Ammonium sulfate ((NH4)2SO4) is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer since the chemical contains 21% nitrogen and 24% sulfur.
- Question 31 of 50
Stains of rust on clothes can be removed by:
Stains of rust on clothes can be removed by oxalic acid (ethanedioic acid). Oxalic acid is widely used as an acid rinse in laundries, where it is effective in removing rust and ink stains because it converts most insoluble iron compounds into a soluble complex ion.
- Question 32 of 50
Ethanol containing 5% water is known as:
Rectified spirit is highly concentrated ethanol that has been purified by means of repeated distillation in a process called rectification. It contains 95% ethanol and 5% water.
- Question 33 of 50
Transboundary pollution is caused by:
Transboundary pollution is the pollution that originates in one country but is able to cause damage to another country’s environment, by crossing borders through pathways like water or air. It is caused by a chemical reaction that begins when compounds like sulfur dioxide (SO2) and nitrogen oxides (NOx) are released into the air. Acid rain is an example of Transboundary pollution.
- Question 34 of 50
The natural disaster in which carbon dioxide suddenly erupts from deep lake water is known as:
A limnic eruption (lake overturn) is a natural disaster in which dissolved carbon dioxide suddenly erupts from deep lake waters, forming a gas cloud capable of suffocating wildlife, livestock, and humans.
- Question 35 of 50
Dry ice is nothing but:
Dry Ice is the common name for solid carbon dioxide (CO2). It gets this name because it does not melt into a liquid when heated; instead, it changes directly into a gas (a process known as sublimation).
- Question 36 of 50
Which one of the following is obtained as slag in a blast furnace?
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron. Blast furnace slag is a nonmetallic coproduct produced in the process. It consists primarily of silicates, aluminosilicates, and calcium-alumina-silicates.
- Question 37 of 50
When H2 gas is allowed to expand from a region of high pressure to a region of low pressure the temperature of the gas:
When a gas is expanded from a high-pressure region to a low-pressure region; temperature change occurs. This phenomenon is related to the Joule-Thomson effect. The inversion temperature of hydrogen is low thus it shows heating effect (increase in temperature) when it expands adiabatically from high pressure into a region of low pressure.
- Question 38 of 50
In the industrial production of vegetable ghee, the process involved is:
The process involved in the industrial production of vegetable ghee is reduction. Vegetable ghee is made from cooking oil by hydrogenation. Hydrogenation reaction of unsaturated fatty acids is basically the reaction where the hydrogen gets added in the double bond of the alkene or alkyne in presence of nickel. Nickel acts like a catalyst in solid-state.
- Question 39 of 50
Which of the following weeds has been found useful to check water pollution caused by industrial affluents?
Water hyacinth (Eichhornia crassipes) is used for cleansing polluted water bodies owing to its remarkable capacity of absorbing pollutants.
- Question 40 of 50
Pyroligneous acid obtained from wood contains:
Pyroligneous acid, also called wood vinegar or wood acid, is a dark liquid produced by the destructive distillation of wood and other plant materials. The principal components of pyroligneous acid are 10% acetic acid, acetone and methanol.
- Question 41 of 50
Which of the following pairs is correctly matched?
The chemical name of Gypsum is calcium sulphate dihydrate (CaSO4⋅2H2O). Milk of lime is the common name for saturated calcium hydroxide solution (Ca(OH)2). Glauber’s salt is the common name for sodium sulfate decahydrate (Na2SO4·10H2O). Saltpeter is one name for the compound called potassium nitrate, which has the chemical formula KNO3.
- Question 42 of 50
Which is not a correct statement?
Methylated spirit is a mixture of ethyl alcohol (95%) and methyl alcohol (%5). The methyl alcohol is poisonous and is added to prevent the methylated spirits from being used as cheap drinking alcohol.
- Question 43 of 50
Which of the following could be used as fuel in propellant or rockets?
Rocket engines and boosters carry both fuel and an oxidizer. For solid fuel, the components are aluminum and ammonium perchlorate. For liquid fuel, the components are liquid hydrogen and liquid oxygen. When combined, the fuels release water, which allows the rocket to leave the ground.
- Question 44 of 50
The addition of gypsum to portland cement helps in:
Gypsum is a mineral and is hydrated calcium sulphate in chemical form. It slows down the hydration process of cement once it is mixed with water. It is mainly used for preventing the rapid setting of cement.
- Question 45 of 50
The Refrigerant ‘FREON’ is:
Dichlorodifluoromethane (CCl2F2) is sold under the brand name Freon-12. Freon is a non-combustible gas that is used as a refrigerant in air conditioning applications. It is a non-corrosive gas belonging to the class of chlorofluorocarbons (CFCs).
- Question 46 of 50
Hard steel contains:
Hard steel contains 0.5 to 1.5 percent carbon. Typically there is less than 0.40% carbon in most steels, though it is possible to have as much as 2%. Once the carbon content exceeds 0.65%, additional carbon can enhance the steel’s hardenability and improve performance.
- Question 47 of 50
Cement is formed by strongly heating a mixture of:
Cement is formed by strongly heating a mixture of limestone and clay. Cement manufacturing is a complex process that begins with mining and then grinding raw materials that include limestone and clay, to a fine powder, called raw meal, which is then heated to a sintering temperature as high as 1450 °C in a cement kiln.
- Question 48 of 50
Glass is a:
Glass is a supercooled liquid. When glass is made, the material (often containing silica) is quickly cooled from its liquid state but does not solidify when its temperature drops below its melting point. At this stage, the material is a supercooled liquid, an intermediate state between liquid and glass.
- Question 49 of 50
The temperature of the oxy-acetylene flame is around:
The temperature of the oxy-acetylene flame is around 3200°C. Oxy-acetylene welding, commonly referred to as gas welding, is a process which relies on combustion of oxygen and acetylene. When mixed together in correct proportions within a hand-held torch or blowpipe, a relatively hot flame is produced with a temperature of about 3200°C.
- Question 50 of 50
The gas that is used in the manufacture of vanaspati ghee is:
The gas that is used in the manufacture of vanaspati ghee is hydrogen. Hydrogenation is a process where manufacturers add hydrogen to a liquid fat, such as vegetable oil, to turn it into a solid fat at room temperature.