Description : How many of the following metals can be extracted buy carbon reduction method ? Na,Al,Mg,Sn,Fe,Pb,Zn,Ca
Last Answer : How many of the following metals can be extracted buy carbon reduction method ? Na,Al,Mg,Sn,Fe,Pb,Zn,Ca
Description : Give reason: a) Metals are electropositive. b) Non-metals are electronegative. c) Even though hydrogen is a non-metal, it is electropositive. d) Sodium is electropositive.
Last Answer : a) Metals are electropositive. Electropositive element has the tendency to lose electrons and form cation.Metals are electron donors. Hence they are electropositive. b) Non-metals are ... is electropositive because donates electrons from last orbit to another element and becomes electropositive.
Description : How the most electropositive metals are isolated from their ores ?
Last Answer : Ans. The most electropositive metals are isolated from their ores by electrolysis of fused ionic salts.
Description : Aluminium is extracted from bauxite (a) By reduction with carbon (b) By reduction with Mg (c) By reduction with CO (d) By electrolysis in molten cryolite
Last Answer : Ans:(d)
Description : Metals which can be extracted by smelting process are :
Last Answer : Metals which can be extracted by smelting process are : A. Zns B. Al C. Pb D. Fe
Description : The study of metals and the overall process by which metals are extracted from its ores are called?
Last Answer : Metallurgy
Description : Which metals are generally extracted by electrolyte process? Which positions these metals generally occupy in the periodic table?
Last Answer : Ans. : Electrolytic process is used for the extraction of active metals like Na, Ca, Mg, K, Al etc. where all other methods fail. Except Al and few other metals, these metals belongs to S-block elements of periodic table.
Description : Which metal is extracted by thermal reduction process? -Do You Know?
Last Answer : answer:
Description : Among the sulphide oers of Ag,Hg,Pb,Fe Cu anZn how many of them can be extracted by self reduction process.
Last Answer : Among the sulphide oers of Ag,Hg,Pb,Fe Cu anZn how many of them can be extracted by self reduction process.
Description : Minerals from which metals can be extracted economically and easily are called ores. The extraction of metals from theirs ores involves the following
Last Answer : Minerals from which metals can be extracted economically and easily are called ores. The ... . D. roasting followed by electrolytic reduction.
Last Answer : Minerals from which metals can be extracted economically and easily are called ores. The extraction of metals from ... 2)S+2Cu_(2)O rarr 6Cu+SO_(2)`
Description : Is it true that many metals are extracted from ores that contain sulfide minerals?
Last Answer : Feel Free to Answer
Description : Metals extracted from sea water?
Last Answer : Magnesium and sodium
Description : How many of the given metals can be obtained by carbon reduction in their extractive metallurgy
Last Answer : How many of the given metals can be obtained by carbon reduction in their extractive metallurgy
Description : Which of the following metals is NOT obtained by reduction using carbon? (1) Copper (2) Sodium (3) Iron (4) Zinc
Last Answer : (2) Sodium Explanation: Metals such as zinc, iron and copper are present in ores as their oxides. Each of these oxides is heated with carbon to obtain the metal.
Description : The most electropositive metal among the following is
Last Answer : The most electropositive metal among the following is A. Zns B. Fe C. Ca D. Na
Description : Assertion : Hydrometallurgy involves dissolving the ore in a suitable reagent followed by precipitation by a more electropositive metal. Reason : Copp
Last Answer : Assertion : Hydrometallurgy involves dissolving the ore in a suitable reagent followed by precipitation ... : Copper is extracted by hydrometallurgy.
Description : The most electropositive metal are isolated from their ores by
Last Answer : The most electropositive metal are isolated from their ores by A. High temperature reduction ... decomposition D. Electrolysis of fused ionic salts
Description : The least electropositive metal among the following is
Last Answer : The least electropositive metal among the following is A. Au B. Mg C. Al D. Zn
Description : The most electropositive element among the following is (a) Na (b) Ca (c) K (d) Cs
Description : The most electropositive elements among the following is : (1) Cs (2) Ca (3) Na (4) Br
Last Answer : (1) Cs Explanation: The alkali metals are the most electropositive. Cesium is the most electropositive of the stable elements.Francium, while unstable, is theoretically the most electropositive element.
Description : Most electropositive elements?
Last Answer : Francium or Caesium
Description : In which of the following pair(s) the minerals are converted in to metals by self-reduction process?
Last Answer : In which of the following pair(s) the minerals are converted in to metals by self-reduction process? A. `Cu_(2)S, ... `PbS, ZnS` D. `Ag_(2)S, Cu_(2)S`
Description : Heavy water used in the nuclear reactors to slow down the speed of neutrons is (A) Highly purified water (B) A compound of oxygen and deuterium (C) Water having dissolved salts of heavy metals (D) None of these
Last Answer : (B) A compound of oxygen and deuterium
Description : Hydrochloric acid is __________ corrosive to common metals. (A) Least (B) Not (C) Mildly (D) Highly
Last Answer : (D) Highly
Description : Which is NOT a characteristic of emissivity? A. It is high with most nonmetals B. It is directly proportional to temperature C. It is independent with the surface condition of the material D. It is low with highly polished metals
Last Answer : It is independent with the surface condition of the material
Description : Which of the following is false? a) electricity is high-grade energy b) high grade forms of energy are highly ordered and compact c) low grade energy is better used for applications like melting of metals rather than heating water for bath
Last Answer : c) low grade energy is better used for applications like melting of metals rather than heating water for bath
Description : Why alkali metals are highly electro positive & they are not found in free state ?
Last Answer : The loosely held s-electron in the outermost valence shell of these elements makes them the most electropositive metals. They readily lose electron to give monovalent M+ ions. Hence they are never found in free state in nature.
Description : The following statement(s) is/are true concerning HIV infection. a. Initial screening with ELISA is highly sensitive but can be associated with a false positive rate of 25% b. ... , carinii pneumonia, CMV pneumonitis, Cryptococcus meningitis, and disseminated infection due to atypical mycobacteria
Last Answer : Answer: b, c, d Acquired immunodeficiency syndrome (AIDS) is a syndrome caused by the human retrovirus (HIV-1) that infects T lymphocytes and causes severe immunosuppression. Individuals who ... to prolong survival when administered early in the course of disease and is considered routine therapy
Description : Which of the following principles or guidelines accurately informs the nurse regarding placebos? a) Placebos should never be used to test the person's truthfulness about pain. Perception of pain is highly ... placebo should never be interpreted as an indication that the person's pain is not real.
Last Answer : a) Placebos should never be used to test the person’s truthfulness about pain. Perception of pain is highly individualized.
Description : Whole circle bearing of a line is preferred to a quadrantal bearing merely because (A) Bearing is not completely specified by an angle (B) Bearing is completely specified by an angle ... different in different quadrants (D) Its Trigonometrical values may be extracted from ordinary tables easily
Last Answer : (B) Bearing is completely specified by an angle
Description : For how many metals of `10^(th)`12 th and `14^(th)` groups in periodic chart, Extraction is possible by self - reduction mrthod ?
Last Answer : For how many metals of `10^(th)`12 th and `14^(th)` groups in periodic chart, Extraction is possible by self - reduction mrthod ?
Description : Which of the following reduction reactions are actually employed in commercial extraction of metals ?
Last Answer : Which of the following reduction reactions are actually employed in commercial extraction of metals ? A. `Fe_(2 ... + 2CuO rarr 3Cu + SO_(2) uparrow `
Description : Statement-1: Auto reduction of ores is used for cinnabar, copper glance and Galena ores Statement-2:The sulphide ores of these metals react with their
Last Answer : Statement-1: Auto reduction of ores is used for cinnabar, copper glance and Galena ores Statement-2: ... Statement-1 is false but Statement -2 is true
Description : Which of the following reduction reactions are actually employed in commercial extraction of metals?
Last Answer : Which of the following reduction reactions are actually employed in commercial extraction of metals? A. `Fe_(2)O_(3 ... (2)S + 2CuO rarr 6Cu + SO_(2)`
Description : Standard reduction potential of alkali metals have high negative values.
Last Answer : Explain : Standard reduction potential of alkali metals have high negative values.
Description : Exposure to SO2 containing chimney gases results in the (A) Reduction in strength of leather & cloth (B) Acceleration of corrosion rates of metals (C) Increased drying & hardening time of paints (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The elements extracted through the process of distillation?
Last Answer : Zinc and Mercury
Description : Carbon cannot be used in the reduction of `A1_(2)O_(3)` because:
Last Answer : Carbon cannot be used in the reduction of `A1_(2)O_(3)` because: A. it is non-metal B. the heat of ... heat of formation of `Al_(2)O_(3)` is too high
Last Answer : Carbon cannot be used in the reduction of `A1_(2)O_(3)` because: A. ZnO B. `SnO_(2)` C. `Fe_(2)O_(3)` D. `Al_(2)O_(3)`
Description : Assertion : Reduction of ZnO with carbon is done at `1100^(@)C`. Reason : At this temperature, `DeltaG^(@)` is negative and the process is spontaneous
Last Answer : Assertion : Reduction of ZnO with carbon is done at `1100^(@)C`. Reason : At this temperature, ... ^(@)` is negative and the process is spontaneous.
Description : Why carbon reduction process is not applied for reducing aluminium oxide to aluminium ?
Last Answer : Ans. Because aluminium metal itself a very powerful agent and can easily reduce CO formed during the reaction back to carbon.
Description : The product of a commercial direct reduction process is (A) Liquid iron (B) Solid iron (C) Sponge iron (D) Iron saturated with carbon
Last Answer : (C) Sponge iron
Description : During the charging process of storage batteries, the charging rooms should be well ventilated because __________. A. without ventilation excessive gassing will occur B. highly poisonous gases are ... gases will otherwise accumulate D. without ventilation the battery will not take a full charge
Last Answer : Answer: C
Description : Battery charging rooms should be well ventilated because the charging process produces_____________. A. highly poisonous gas B. highly combustible oxygen C. explosive gases D. corrosive gases