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 : Primary alcohol cannot be prepared by the reduction of
Last Answer : Primary alcohol cannot be prepared by the reduction of A. aldehyde B. acid C. Ketone D. ester
Description : When comes down to stress reduction, which one is preferred? a) Solid flywheel b) Split flywheel c) Both have equal stresses d) Cannot be determined
Last Answer : b) Split flywheel
Description : Pick out the wrong statement about cavitation. (A) Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation ... (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades
Last Answer : (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades
Description : Which of the following statements is false about benzylamine? (a) can be prepared by reduction of benzonitrile with LiAlH4. (b) cannot be prepared by reduction of benzamide with LiAlH4. (c) reacts with nitrous acid to give benzyl alcohol. (d) reacts with KMnO4 to give benzoic acid.
Last Answer : cannot be prepared by reduction of benzamide with LiAlH
Description : Which metal is extracted by thermal reduction process? -Do You Know?
Last Answer : answer:
Description : Statement -1 : Ores are generally converted into oxides , prior to reduction . Statement- 2 : Metal oxides can be easily reduced .
Last Answer : Statement -1 : Ores are generally converted into oxides , prior to reduction . Statement- 2 : Metal oxides ... -1 : is false , statement-2 : is true
Description : Statement-1: The reduction of a metal oxide is easier if the metal formed is in liquid state at the temperature of reduction. Statement-2: The value o
Last Answer : Statement-1: The reduction of a metal oxide is easier if the metal formed is in liquid state at ... . Statement-1 is false but Statement -2 is true
Description : In the extraction of Cu from its sulphide ore, the metal is formed by reduction of `Cu_(2)O` with
Last Answer : In the extraction of Cu from its sulphide ore, the metal is formed by reduction of `Cu_(2)O` with A. FeS B. CO C. `Cu_(2)S` D. `SO_(2)`
Description : (A) Auto reduction of ore is used for the extraction of copper (R ) The sulphide ore of copper reacts with its oxide to the give the metal
Last Answer : (A) Auto reduction of ore is used for the extraction of copper (R ) The sulphide ore of copper reacts ... . If (A) is incorrect but (R ) is correct
Description : Which of the followigng metal is obtained by the reduction of metal oxide with Hydrogen gas
Last Answer : Which of the followigng metal is obtained by the reduction of metal oxide with Hydrogen gas A. Cu B. Al C. Mg D. Fe
Description : In extractive metallurgy of lead, the reduction of the roasted ore to the molten metal by heating with coke is called
Last Answer : In extractive metallurgy of lead, the reduction of the roasted ore to the molten metal by heating with ... B. roasting C. calcination D. None of these
Description : (3) made cathode and a pure nickel red, the anode Explanation: Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be ... on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
Last Answer : Which of the following is not a method of preparing oxygen? (1) Electrolysis of water (2) Fractional distillation of liquid air (3) Decomposition of potassium permanganate (4) Decomposition of manganese dioxide
Description : Although thermodynamically feasible, in practice, Magnesium metal is not used for the reduction of Alumina in the metallurgy of aluminium.Why?
Last Answer : Ans. : Below the temperature(1623 K) correspoinding to the point of intersection of Al 2O3 and MgO curves in Ellingham diagram, Magnesium can reduce Alumina because the ΔfG o value of Al2O3 at ... to Al. But Magnesium is much costier metal than Aluminium and hence the process will be uneconomical.
Description : Flux addition during smelting of ore is done to (A) Remove impurities/gangue (B) Enhance rate of reaction (C) Accelerate reduction of ore (D) Separate slag from metal
Last Answer : (A) Remove impurities/gangue
Description : An advantage of metal. ceramic crowns, compared wit full ceramic crowns for restoring anterior teeth is, A. Palatal reduction may be of minimal thickness. B. Overall conservative for tooth structure. C. Ability to watch the appearance of adjacent natural teeth. D. Less laboratory time.
Last Answer : A. Palatal reduction may be of minimal thickness.
Description : What is the minimal labial reduction for porcelain metal crowns: A. 1mm B. 1.5mm C. 0.5mm
Last Answer : B. 1.5mm
Description : The minimal labial tooth reduction for satisfactory aesthetics with porcelain fused to metal crown is, A. 1mm B. The full thickness of enamel C. 1.5 mm D. 2.5mm E. One third of the dentine thickness
Last Answer : C. 1.5 mm
Description : An advantage of metal-ceramic crowns, compared wit full ceramic crowns for restoring anterior teeth is, A. Palatal reduction may be of minimal thickness B. Overall conservative for tooth structure C. Ability to watch the appearance of adjacent natural teeth D. Less laboratory time
Last Answer : A. Palatal reduction may be of minimal thickness
Description : The correct sequence of steps involved in extraction of metal from its ore is a) removal of impurities, purify metal, reduction of ore b) purify metal, removal of impurities, reduction of metal ore . c ... of metal , reduction d) removal of impurities from ore , reduction of ore , refining of metal
Last Answer : d) removal of impurities from ore , reduction of ore , refining of metal
Description : What property of a metal describes the onset of plastic deformation in a tensile test? w) tensile strength x) elongation y) yield strength z) reduction in area
Last Answer : ANSWER: Y -- YIELD STRENGTH
Description : What is reduction of oxide with carbon at high temperature called? -General Knowledge
Last Answer : The answer is 'Smelting'
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 : 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 : The carbon-based reduction method is NOT used for the extraction of
Last Answer : The carbon-based reduction method is NOT used for the extraction of A. Tin From `SnO_(2)` B. Iton from ... 3)` D. Mangnesium from `MgCO_(3).CaCO_(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 : Highly electropositive metals can not be extracted by carbon reduction process because these :
Last Answer : Highly electropositive metals can not be extracted by carbon reduction process because these : A. Metals ... D. Loss of metal is more by vaporisation
Description : The disadvantage of carbon reduction method are :
Last Answer : The disadvantage of carbon reduction method are : A. high temperature needed which is ... carbon cannot be used with highly electropositive metals
Description : Which of the following faction is of no significance for roasting sulphide ores to the oxide and not subjecting the sulphide ores in carbon reduction
Last Answer : Which of the following faction is of no significance for roasting sulphide ores to the oxide and ... are thermodynamically more stable than `CS_(2)`
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 : If the body undergoes alkalosis the respiratory center located in the medulla gets the information and induces the lowering of the respiratory frequency. The reduction of the respiratory frequency makes ... of bicarbonate towards the production of more hydrogen ions and thus the blood pH lowers.
Last Answer : What is the difference between respiratory acidosis and metabolic acidosis and what is the difference between respiratory alkalosis and metabolic alkalosis?
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 : Petroleum coke is used mainly in the (A) Discoloration of yellow glycerine (B) Sugar refining (C) Manufacture of carbon electrode (D) Blast furnace for reduction of iron ore
Last Answer : (C) Manufacture of carbon electrode
Description : Maximum use of petroleum coke is in (A) Adsorption refining operation (B) Fuel gas manufacture (C) Carbon electrode manufacture (D) Iron ore reduction
Last Answer : (C) Carbon electrode manufacture
Description : At which temperature direct reduction of Fe2O3 by carbon is possible ?
Last Answer : Ans. Above 1123 K, carbon can reduce Fe2O3
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 : Electrolytic reduction cell used for conversion of calcined Al2O3to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to (A) Achieve very high ... by the generation of heat (C) Electrolytically dissociate alumina (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
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 : The reduction of the PH value, by the action of atmospheric carbon dioxide with the alkali of the cement paste is called [ A ] atmospheric corrosion [ B ] chloride corrosion [ C ] oxidation [ D ] carbonation
Last Answer : [ D ] carbonation