McqMate
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: General Knowledge (GK) .
| 301. |
Which one of the following organic compound is used to remove stains of iron compounds? |
| A. | Oxalic acid |
| B. | Benzoic acid |
| C. | Phthalic acid |
| D. | Cinnamic acid |
| Answer» A. Oxalic acid | |
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Explanation: Oxalic acid is a reducing agent and its conjugate base, known as oxalate is a chelating agent for metal cations. Oxalic acid's main applications include cleaning or bleaching, especially for the removal of rust, e.g. Bar Keepers Friend is an example of a household cleaner containing oxalic acid. Its utility in rust removal agents is due to its forming a stable, water soluble salt with ferric iron, ferrioxalate ion. |
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| 302. |
Which one of the following pairs is NOT correctly matched? |
| A. | Haematite : Copper |
| B. | Bauxite : Aluminium |
| C. | Monazite : Thorium |
| D. | Pitchblende : Uranium |
| Answer» A. Haematite : Copper | |
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Explanation: Haematite is the mineral form of iron oxide (Fe2O3), one of several iron oxides. It is mined as the main ore of iron. Hematite is harder than pure iron, but much more brittle. |
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| 303. |
Which of the following is used for refrigeration? |
| A. | Sulphur dioxide |
| B. | Chlorine |
| C. | Freon |
| D. | Phosphine |
| Answer» C. Freon | |
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Explanation: Common refrigerants used in domestic refrigerators are Freon, neon and nitrogen. It flows through four components of refrigerator again and again. |
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| 304. |
Electrons in the highest energy level of an atom are called . |
| A. | valence protons |
| B. | orbital protons |
| C. | valence electrons |
| D. | orbital electrons |
| Answer» C. valence electrons | |
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Explanation: The outermost orbital shell of an atom is called its valence shell, and the electrons in the valence shell are valence electrons. |
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| 305. |
Bromine is- |
| A. | Colorless gas insoluble in water |
| B. | A highly inflammable gas |
| C. | A Black solid |
| D. | A red liquid |
| Answer» D. A red liquid | |
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Explanation: Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming liquid with a deep red color. At room temperature, Bromine evaporates readily to form a red to amber colored gas. |
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| 306. |
Which is not a type of elements? |
| A. | Metals |
| B. | Non Metals |
| C. | Metalloids |
| D. | Gases |
| Answer» C. Metalloids | |
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Explanation: Element is a chemical substance consisting of atoms having the same number of protons in their atomic nuclei. There are 118 elements that have been identified. The elements classified as metalloids are boron, silicon, germanium, arsenic, antimony, tellurium and polonium. |
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| 307. |
Which among the following is used in making liquors, medicines and as a fuel in aircrafts? |
| A. | Propyl alcohol |
| B. | Dimethyl alcohol |
| C. | Ethyl alcohol |
| D. | Methyl alcohol |
| Answer» C. Ethyl alcohol | |
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Explanation: Ethyl alcohol (C2H5), also known as ethanol, is a member of a class of organic compounds that are given the general name alcohols. |
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| 308. |
The nuclear particles which are assumed to hold the nucleons together are - |
| A. | positrons |
| B. | neutrons |
| C. | electrons |
| D. | mesons |
| Answer» D. mesons | |
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Explanation: The nuclear particles which are assumed to hold the nucleons together are mesons. |
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| 309. |
Milk of magnesia is a suspension of – |
| A. | magnesium sulphate |
| B. | magnesium carbonate |
| C. | magnesium hydroxide |
| D. | magnesium Chloride |
| Answer» C. magnesium hydroxide | |
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Explanation: Milk of magnesia is a suspension of magnesium hydroxide due to its milk-like appearance. |
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| 310. |
Which of the following cannot be beaten into Sheets? |
| A. | Gold |
| B. | Silver |
| C. | Potassium |
| D. | Aluminium |
| Answer» C. Potassium | |
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Explanation: Substances that can be beaten into thin sheets are called malleable. Most metals are malleable. |
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| 311. |
Minamata disease is a nervous disorder caused by eating fish, polluted with |
| A. | Iron |
| B. | Lead |
| C. | Mercury |
| D. | Nickel |
| Answer» C. Mercury | |
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Explanation: Minamata disease is a neurological syndrome caused by severe mercury poisoning Symptoms include ataxia numbness in the hands and feet, general muscle weaknes narrowing of the field of vision and damage to hearing and speech. |
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| 312. |
Which of the following is used to denature ethanol? |
| A. | Methyl alcohol |
| B. | Propyl alcohol |
| C. | Phenol |
| D. | Methane |
| Answer» A. Methyl alcohol | |
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Explanation: Denatured alcohol is ethanol that has additives to make it undrinkable (poisonous), to discourage recreational consumption. Different additives are used to make it difficult. to use distillation or other simple processes to reverse the denaturation. |
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| 313. |
The charcoal used to decolorize brown sugar solution is |
| A. | Wood charcoal |
| B. | Coconut charcoal |
| C. | Animal charcoal |
| D. | Sugar charcoal |
| Answer» C. Animal charcoal | |
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Explanation: A special characteristic of animal charcoal is its power to remove substances from solution. A brown solution of raw sugar is decolourized when boiled with animal charcoal. Other substances that are similarly removed from solution are indigo, litmus, iodine, the colouiing-matter of red wine, the brown matter of peaty water or sewage, astringent principles, and certain basic salts, etc. |
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| 314. |
Which one of the following is used as a sowing agent in the preparation of soft drinks? |
| A. | Phosphoric acid |
| B. | Phosphorus acid |
| C. | Salicylic acid |
| D. | Boric acid |
| Answer» A. Phosphoric acid | |
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Explanation: Phosphoric acid was the foundation of the soft-drink industry, long before Coca-Cola's popularity. Phosphoric acid is deliberately added to soft drinks to give them a sharper flavor. It also slows the growth of molds and bacteria, which would otherwise multiply. |
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| 315. |
The coating of a thin layer of zinc on steel or iron objects is known as – |
| A. | Hot dipping |
| B. | Tinning |
| C. | Galvanising |
| D. | Electroplating |
| Answer» C. Galvanising | |
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Explanation: Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are submerged in a bath of molten zinc. |
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| 316. |
Which of the following produces highest amount of energy upon oxidation? |
| A. | Protein |
| B. | Fat |
| C. | Glucose |
| D. | An alkane |
| Answer» B. Fat | |
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Explanation: Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure and composition. Although the words "oils", "fats", and "lipids" are all used to refer to fats, "oils" is usually used to refer to fats that are liquids at normal room temperature, while "fats" is usually used to refer to fats that are solids at normal room temperature. |
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| 317. |
Which of the following substance is highly plastic? |
| A. | Quartz |
| B. | Mica |
| C. | Granite |
| D. | Clay |
| Answer» D. Clay | |
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Explanation: Clays exhibit plasticity when mixed with water in certain proportions. When dry, clay becomes firm and when fired in a kiln, permanent physical and chemical changes occur. These reactions, among other changes, cause the clay to be converted into a ceramic material. Because of these properties, clay is used for making pottery items, both utilitarian and decorative. Different types of clay, when used with different minerals and firing conditions, areused to produce earthenware, stoneware, and porcelain. |
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| 318. |
The National Chemical Laboratory (India) is located in – |
| A. | Mumbai |
| B. | Bangaluru |
| C. | Hyderabad |
| D. | Pune |
| Answer» D. Pune | |
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Explanation: NCL, India is a research, development and consulting organization with a focus on chemistry and chemical engineering. It has a successful record of research partnership with industryand is located in pune. NCL belongs to the family of Council of Scientific and Industrial Research (CSIR), the largest chain of public funded research organization in world. NCL's human resources comprise of over 1000 people of whom 350 are scientist, 110 are technical staff with advanced degrees in science, technology or engineering. |
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| 319. |
The major constituent of gobar gas is – |
| A. | Carbon dioxide |
| B. | Methane |
| C. | Butane |
| D. | Isobutane |
| Answer» B. Methane | |
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Explanation: lobar Gas (Methane) is generated by the decomposition of organic cow dung. It consists of 55-65% methane, 30-35% carbon dioxide, with some hydrogen, nitrogen and other traces. The composition of biogas varies depending upon the origin of the anaerobic digestion process. Landfill gas typically has methane concentrations around 50%. |
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| 320. |
The residue left after extracting juice from sugar beet and sugarcane is called – |
| A. | molasses |
| B. | bagasse |
| C. | whey |
| D. | biomass |
| Answer» B. bagasse | |
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Explanation: Bagasse is the fibrous matter that remains after sugarcane or sorghum stalks are crushed to extract their juice. It is currently used as a biofuel and in the manufacture of pulp and paper products and building materials. Agave bagasse is a similar material that consists of the, tissue of the blue agave after extraction of the sap. For each 10 tonnes of sugarcane crushed, a sugar factory produces nearly 3 tonnes of wet bagasse. Since bagasse is a by-product of the cane sugar industry, the quantity of production in each country is in line with the quantity of sugarcane produced. |
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| 321. |
Indane gas is a mixture of which gases? |
| A. | butane and hydrogen |
| B. | butane and propane |
| C. | butane and oxygen |
| D. | methane and oxygen |
| Answer» B. butane and propane | |
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Explanation: 0 |
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| 322. |
Who among the following discovered electron? |
| A. | J.J Thomson |
| B. | Max Born |
| C. | Antoine Lavoisier |
| D. | Mendeleef |
| Answer» A. J.J Thomson | |
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Explanation: Electron was discovered by J. J. Thomson in 1897 when he was studying the properties of cathode ray. |
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| 323. |
Nuclear fission is caused by the impact of - |
| A. | Proton |
| B. | Electron |
| C. | Neutron |
| D. | None of these |
| Answer» C. Neutron | |
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Explanation: Nuclear fission in fissile fuels are the result of the nuclear excitation energy produced when a fissile nucleus captures a neutron. |
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| 324. |
Acid rain is due to air pollution by - |
| A. | Carbon dioxide |
| B. | Carbon monoxide |
| C. | Methane |
| D. | Nitrous oxide and Sulfur dioxide |
| Answer» D. Nitrous oxide and Sulfur dioxide | |
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Explanation: The main chemicals in air pollution that create acid rain are sulfur dioxide (SO2) and Nitrous oxide (N2O). |
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| 325. |
Milk is a natural – |
| A. | Solution |
| B. | Emulsion |
| C. | Mixture |
| D. | Suspension |
| Answer» B. Emulsion | |
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Explanation: An emulsion is a mixture of two or more liquids that are normally immiscible (nonmixable or unblendable). Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion should be used when both the dispersed and the continuous phase are liquids. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase). |
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| 326. |
A polymeric substance used to make parachute is – |
| A. | Rayon |
| B. | Viscose |
| C. | Cotton |
| D. | Terylene |
| Answer» B. Viscose | |
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Explanation: Viscose is a viscous organic liquid used to make rayon and cellophane. Viscose is also used as shorthand for Viscose Rayon, thus becoming synonymous with rayon, a soft man-made fibre commonly used in dresses, linings shirts, shorts, coats, jackets, and other outer wear. |
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| 327. |
The metallic Constituents of hard water are – |
| A. | Magnesium, calcium and tin |
| B. | Iron, tin and calcium |
| C. | Calcium, magnesium and iron |
| D. | Magnesium, tin and iron |
| Answer» C. Calcium, magnesium and iron | |
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Explanation: Hard water is water that has high mineral content. In domestic settings, hard water is often indicated by a lack of suds formation when soap is agitated in water. Wherever water hardness is a concern, water softening is commonly used to reduce hard water's adverse effects. |
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| 328. |
The pH of human blood is between – |
| A. | 6.5-7 |
| B. | 7.5-8 |
| C. | 8-9 |
| D. | 4.5-5 |
| Answer» B. 7.5-8 | |
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Explanation: Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells. Blood pH is regulated to stay within the narrow range of 7.5 to 8. Blood that has a pH below 7.5 is too acidic, whereas blood pH above 7.5 is too alkaline. |
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| 329. |
Which of the following is used as a lubricant in heavy machines? |
| A. | Bauxite |
| B. | Sulphur |
| C. | Phosphorus |
| D. | Graphite |
| Answer» D. Graphite | |
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Explanation: Graphite is used as a lubricant in heavy machines. it is made of carbon atoms arranged in sheets of hexagonal units - looks a lot like chicken-wire. Another sheet forms on top of this and so on. There is no proper connection (in ideal graphite) between thesheets, so they are able to slide freely over each other without breaking any bonds. |
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| 330. |
What is the element that is in the highest percentage in the composition of the earth? |
| A. | Silicon |
| B. | Oxygen |
| C. | Magnesium |
| D. | Iron |
| Answer» B. Oxygen | |
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Explanation: Earth, our home, is the third planet from the sun. It is the only planet known to have an atmosphere containing free oxygen, oceans of liquid water on its surface, and, of course, life. Earth is the fifth largest of the planets in the solar system smaller than the four gas giants, Jupiter, Saturn, Uranus and Neptune, but larger than the three other rocky planets, Mercury, Mars and Venus. Roughly 71 percent of Earth's surface is covered by water, most of it in the oceans. About a fifth of its atmosphere is made up of oxygen, produced by plants. |
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| 331. |
Formation of ozone hole is maximum over – |
| A. | Africa |
| B. | India |
| C. | Antarctica |
| D. | Europe |
| Answer» C. Antarctica | |
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Explanation: A continent sized hole (thinning) has been formed over Antarctica as a result of damage to ozone. Most ozone is formed in the stratosphere over the equation and spread by winds around the globe. Icy particles in polar stratospheric clouds catalyze the release of chlorine (from CFC) which destroys ozone. The thinning of ozone is maximum because winter there is exceptionally cold. |
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| 332. |
Which of the following is used to iodise common salt? |
| A. | Potassium iodide |
| B. | Iodine |
| C. | Potassium iodate |
| D. | Sodium iodide |
| Answer» C. Potassium iodate | |
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Explanation: Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. Table salt with iodide salt slowly loses its iodine content through the process of oxidation and iodine evaporation. Edible salt can be iodised by spraying it with a potassium iodate solution. 60 ml of potassium iodate. |
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| 333. |
Which of the following imparts deep blue colour to glass? |
| A. | Cobalt oxide |
| B. | Cupric oxide |
| C. | Ferrous oxide |
| D. | Nickel oxide |
| Answer» D. Nickel oxide | |
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Explanation: Glass colouring and colour marking may be obtained by addition of colouring ions, by precipitation of nanometer sized colloides (so-called striking glasses such as "ruby gold" or red "selenium ruby"), by coloured inclusions (as in milk glass and smoked glass). |
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| 334. |
Which of the following fibres catches fire least? |
| A. | Nylon |
| B. | Cotton |
| C. | Rayon |
| D. | Terricot |
| Answer» B. Cotton | |
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Explanation: The fibre least prone to catch fire is cotton. Fabrics with more of the fiber surface area exposed to air have more oxygen availableto support, burning and therefore burn more easily. Thus, thin, gauzy fabrics, lace, or brushed fabrics can be very flammable. |
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| 335. |
Drinking soda is – |
| A. | Alkaline |
| B. | Acidic |
| C. | Neutral |
| D. | Oxidant |
| Answer» B. Acidic | |
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Explanation: A soft drink, coke, soda pop, fizzy drink, tonic, .seltzer, mineral, sparkling water or carbonated beverage) is a beverage that typically contains water (often, but not always carbonated water), usually a sweetener, and usually a flavoring agent. The sweetener may be sugar, high-fructose corn syrup, fruit juice, sugar substitutes (in the case of diet drinks) or a combination of these. Soft drinks may also contain caffeine, colourings, preservatives and other ingredients. Soft drinks are called "soft" in contrast to "hard drinks" (alcoholic beverages). |
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| 336. |
The cathode of a lead storage battery is made up of – |
| A. | Zinc |
| B. | Lead |
| C. | Lead oxide |
| D. | Manganese dioxide |
| Answer» B. Lead | |
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Explanation: Lead-acid batteries, invented in 1859 by French physicist Gaston Plante, are the oldest type of rechargeable battery. Despite having a very low energy-to-weight ratio and a low energy-to-volume ratio, their ability to supply high surge currents means that the cells maintain a relatively large power weight ratio. These features, along with their low cost, make them attractive for use in motor vehicles to provide the high current required by automobile starter motors. |
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| 337. |
Who is regarded as father of modern chemistry? |
| A. | Ruterford |
| B. | Einstein |
| C. | Lavoisier |
| D. | C.V. Raman |
| Answer» C. Lavoisier | |
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Explanation: Antoine Lavoisier is considered the father of modern chemistry. He was a French nobleman who recognized and named oxygen and isolated the major components of air. |
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| 338. |
Kidney stones are mainly formed by which of the following compound - |
| A. | Sodium chloride |
| B. | Silicates |
| C. | Calcium bicarbonate |
| D. | Calcium oxalate |
| Answer» D. Calcium oxalate | |
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Explanation: Kidney stones form when your urine contains more crystal-forming substances — such as calcium, oxalate and uric acid — than the fluid in your urine can dilute. |
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| 339. |
What is the principal ore of aluminium? |
| A. | Dolomite |
| B. | Copper |
| C. | Lignite |
| D. | Bauxite |
| Answer» D. Bauxite | |
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Explanation: Bacodte is an aluminium ore and is the main source of aluminium. This form of rock consists mostly of the minerals gibbsite, boehmite , and diaspore , in a mixture with the two iron oxides goethite and hematite, the clay mineral kaolinite, and small amounts of anatase TiO2. Bauxite was named after the village Les Baux in southern France, where it was first recognised as containing aluminium and named by the French geologist Pierre Berthier in 1821. |
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| 340. |
Which gas is used as fire extinguisher? |
| A. | Carbon dioxide |
| B. | Carbon monoxide |
| C. | Carbon suboxide |
| D. | Sulphur dioxide |
| Answer» A. Carbon dioxide | |
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Explanation: A fire extinguisher, flame extinguisher, or simply an extinguisher, is anactive fire protection device used to extinguish or control small fires, often in emergency situations. Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent which can be discharged. to extinguish a fire. Cartridge-operated extinguishers contain the expellant gas (usually carbon dioxide) in a separate cartridge that is punctured prior to discharge, exposing the propellant to the extinguishing agent. |
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| 341. |
The isotope of Uranium used in atomic reactors is – |
| A. | U^235 (2) |
| B. | U^236 |
| C. | U^237 |
| D. | U^232 |
| Answer» A. U^235 (2) | |
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Explanation: A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid (water or gas), which runs through turbines that power either ship's propellers or generators. Some produce isotopes for medical and industrial use, and some are run only for research. When a large fissile atomic nucleus such as U235 or U239 absorbs a neutron, it may undergo nuclear fission. |
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| 342. |
Which one of the following is not a radioactive element? |
| A. | Uranium |
| B. | Thorium |
| C. | Radium |
| D. | Cadmium |
| Answer» D. Cadmium | |
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Explanation: Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability. Because the nucleus experiences the intense conflict between the two strongest forces in nature, it should not be surprising that there are many nuclear isotopes which are unstable and emit some kind of radiation. The most common types of radiation are called alpha, beta, and gamma radiation, but there are several other varieties of radioactivedecay. Among uranium, thorium, radium and cadmium the first three does show radioactive properties while the fourth one does not show any kind of radioactive properties. |
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| 343. |
The anode in a dry cell consists of – |
| A. | Copper |
| B. | Zinc |
| C. | Cadmium |
| D. | Graphite |
| Answer» B. Zinc | |
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Explanation: A "dry-cell" battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction halfreaction. A thin zinc cylinder serves as the anode and it undergoes oxidation. |
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| 344. |
Aspirin is common name of – |
| A. | Salicylic Acid |
| B. | Salicylate |
| C. | Methyl Salicylate |
| D. | Acetyl Salicylic Acid |
| Answer» D. Acetyl Salicylic Acid | |
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Explanation: Aspirin (USAN), also known as acetylsalicylic acid, is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. Aspirin was first isolated by Felix Hoffmann, a chemist with the German company Bayer in 1897. Aspirin also has an antiplatelet effect by inhibiting the production of thromboxane, which under normal circumstances binds platelet molecules together to create a patch over damaged walls of blood vessels. |
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| 345. |
Carbon monoxide is an inflammable gas. Which one of the following is also inflammable? |
| A. | Helium |
| B. | Nitrogen |
| C. | Oxygen |
| D. | Hydrogen |
| Answer» D. Hydrogen | |
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Explanation: At standard temperature and pressure, hydrogen is a colourless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic has with the molecular formula H2. Naturally occurring atomic hydrogen is rare on Earth because hydrogen readily forms covalent compounds with most elements and is present in the water molecule and in most organic compounds. Hydrogen plays a particularly important role in acid-base chemistry with many reactions exchanging protons between soluble molecules. |
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| 346. |
The constituents of automobile exhaust that can cause cancer is/are : |
| A. | Oxides of nitrogen |
| B. | Carbon monoxide |
| C. | Polycyclic hydrocarbons |
| D. | Lead |
| Answer» B. Carbon monoxide | |
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Explanation: Lead is a naturally occuriing bluish-gray metal found in small amounts in the earth's crust. In the past, when lead was added to gasoline, breathing automobile exhaust was the major source of lead exposure for most people. Lead in the exhaust also contaminated the soil near roads. Another major source a exposure is old paint that contains lead. Lead has been found to be carcinogen. A substance that causes cancer or helps cancer grow is called a carcinogen. |
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| 347. |
Hard steel contains – |
| A. | 2 to 5 per cent carbon |
| B. | 0.5 to 1.5 per cent carbon |
| C. | 0.1 to 0.4 per cent carbon |
| D. | 0.01 to 0.04 per cent carbon |
| Answer» B. 0.5 to 1.5 per cent carbon | |
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Explanation: The term hardened steel is often used for a medium or high carbon steel that has been given the heat treatments of quenching followed by tempering. The quenching results in the formation of metastable martensite, the fraction of which is reduced to the desired amount during tempering. This is the most common state for finished articles such as toolsand machine parts,. In contrast, the same steel composition in annealed state will be softer as required for forming and machining. |
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| 348. |
The metals commonly used for electroplating are – |
| A. | Gold, Sodium and Chromium |
| B. | Chromium, Copper and Nickel |
| C. | Nickel, Lead and Chromium |
| D. | Gold, Sodium and Potassium |
| Answer» B. Chromium, Copper and Nickel | |
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Explanation: The process of electroplating takes place as metals in ionic form move from a positive to negative electrode. An electric current passing through the solution causes objects at the cathode or work piece to be coated by the metal in the solution. Electroplating is done for many reasons, usually to beautify, insulate or to protect and to increase the corrosion resistance, conductivity solder ability of metal objects. Plating protects by one of two ways, either sacrificially or mechanically. |
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| 349. |
Which of the following in auto-mobile exhaust can cause cancer? |
| A. | Oxides of nitrogen |
| B. | Carbon monoxide |
| C. | Lead |
| D. | Polyclinic hydrocarbons |
| Answer» B. Carbon monoxide | |
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Explanation: Polycyclic aromatic hydrocarbons (PAHs) are formed during incomplete combustion. Domestic wood burning and road traffic are the major sources of PAHs. Exposure to PAH-containing substances increases the risk of cancer in humans. The carcinogenicity of PAHs is associated with the complexity of the molecule, i.e., increasing number of benzenoid 'rings, and with metabolic activation to reactive diol epoxide intermediates and their subsequent covalent binding to critical targets in DNA. |
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| 350. |
Which one of the following gases has the highest calorific value? |
| A. | Natural gas |
| B. | Water gas |
| C. | Coal gas |
| D. | Indane gas |
| Answer» D. Indane gas | |
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Explanation: The basic calorific value for solid and liquid fuels is the gross calorific value at constant volume and for gaseous fuels it is the gross calorific value at constant pressure. The calorific value in Kcal/Kg: Coal: 4000-700Q; Natural gas: 8600; Coal gas: 4000; Water gas: 4600-4800; and LPG (liquefied petroleum gas such as Indane): 11,900 Kcal/Kg. |
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