After 13500C, the standard Gibbs free energy of formation of Al2O3 from Al is lower than that of MgO from Mg. As a result, Al can be expected to be able to reduce MgO at temperatures above 13500C.
Vapour phase refining : It is a process of metal refining in which the metal is converted into a volatile compound, which is then decomposed to obtain the pure metal.(1) To accomplish this, the...
It is the process of employing electricity to refine impure metals. The anode is impure metal, and the cathode is a thin sheet of pure metal in this process. The electrolyte is a metal-specific salt...
The premise behind this approach is that contaminants are more soluble in molten metal than in solid metal. A rotating circular heater slowly glides over an impure metal rod or bar in zone refining....
The anode in aluminium electrometallurgy is graphite, and the cathode iron is graphite lined. Electrolysis liberates O2, which combines with the graphite anode to produce CO2 and CO. If it hadn't...
Chlorine is obtained as a byproduct of the Down process. A fused mixture of CaCl2 and NaCl is electrolyzed at 873 K in this method. At the cathode, sodium is obtained, while Cl2 is released at the...
Ans: The graph of Gibbs energy ∆Gθ versus Temperature for the formation of solid oxides is shown above. This graph shows that if the ∆fGθ of a metal's oxide is more negative than the ∆fGθ of another...
At roughly 1673 K, ZnO is converted to Zn. The Gibbs free energy of formation of CO from C is smaller than the Gibbs free energy of formation of ZnO after 1073 K, and the Gibbs free energy of...
Cr2O3 has a higher value of formation ( −540 kJ mol−1 ) than Al2O3 ( −827 kJ /mol ). Therefore, Al can reduce Cr2O3 to Cr. 2Al + (3/2)O2 ⇒ Al2O3 2Cr + (3/2)O2 ⇒ Cr2O3 Subtracting, 2Al +...
CO will not be able to reduce ZnO to Zn because the standard Gibbs free energy of formation of CO to CO2 is larger than that of Zn to ZnO. As a result, CO-assisted zinc oxide reduction is not...
When working with low-grade copper ores, bacteria or acids are utilised to leach the copper in the presence of air. Copper is introduced to the solution as Cu2+ ions in this method: Cu + 2H+ + ½...
The basic functions of Na3AlF6 (Cryolite) are as follows: 1. Due to the presence of cryolite, the melting point of the solution drops from 2323 K to 1140 K. 2. Cryolite makes alumina a good...
Cu2S and FeS are present in copper matte. When a hot blast of air passes through a molten matte in a silica coated converter, the matte's FeS oxidises to FeO. FeSiO3 (slag) is formed when FeO...
Minerals are substances that contain metals or metal compounds and are found in nature. Ores are rocks and minerals that can be mined for metals in a cost-effective and convenient manner. For...
The iron obtained from a blast furnace is known as pig iron. It is 4 percent carbon and contains minor levels of additional impurities such as Si, P, S, and Mn.Cast iron is created by using a hot...
Calcination is the process of converting carbonate and hydroxide ores to oxides by heating them to temperatures below their melting points while avoiding or limiting the presence of air.This...
The following steps are used to separate alumina from silica in bauxite ore that contains silica:To begin, the powdered ore is digested in a concentrated NaOH solution at 473 523 K and 35 36 bar...
Mond's procedure is a nickel refinement technology. Heat is applied to nickel in the presence of carbon monoxide in this process, resulting in nickel tetracarbonyl, a volatile complex. Ni + 4CO ⇒...
The stationary phase is chosen so that the constituents of the mixture have varying degrees of solubility in it. As a result, distinct elements move at different speeds through the phase, allowing...
Chromatography is a term that refers to a group of scientific procedures that are used to purify, separate, characterise, and identify the species in a mixture, whether coloured or colourless. The...
During roasting, copper pyrites are transformed to a combination of Cu2O and FeO. During the smelting process, acidic silica is introduced to separate the FeO from the mixture. FeSiO3 (slag) is...
The various steps involved in zinc extraction are : (1) Concentration of oreZinc blende is crushed first to eliminate impurities from the ore, and then froth flotation is used to concentrate the...
At 500 – 800 K3Fe2O3 +CO → 2Fe3O4 + CO2Fe2O3 +CO → 2FeO + CO2 At 850 KFe3O4 +CO → 3FeO + CO2 At 900 – 1500 KFeO +CO → Fe + CO2CO2 + C → 2CO Above 1570 KC+ O2 → CO2FeO +C → Fe + COCaCO3(s) → CaO(s) +...
During the electrolytic refinement of copper, frequent components found in the anode mud include selenium, silver, tellurium, platinum, antimony, and gold.These metals are almost unaffected by the...
CO is a more effective reducing agent at 673 K because the value of ∆G( C,CO ) is bigger than ∆G( CO,CO2 ), implying that CO is more easily reduced to CO2 than C to CO.
Column chromatography: This is a great way to purify elements that are only present in trace levels. Column chromatography is commonly used to remove impurities that have chemical properties that...
Zone refining: The premise behind this approach is that contaminants are more soluble in molten metal than in solid metal. A rotating circular heater slowly glides over an impure metal rod or bar in...
Copper (I) sulfite has a lower ∆fG (Gibbs free energy of formation) than hydrogen sulfite and carbon disulfite (CS2). As a result, neither C nor H2S will be able to convert Cu2S to Cu.Because...
In froth flotation, the job of a depressant is to separate two sulphide ores by selectively preventing one ore from foaming. For example, to separate two sulphide ores, PbS and ZnS, NaCN is...
Copper's reduction potential is greater than that of zinc or iron. Iron and zinc can thus be employed to remove copper from a solution in hydrometallurgy. Fe(s) + Cu2+(aq) ⇒ Fe2+ (aq) + Cu(s)...