Description : Statement -I :Cryolite is used in electrolytic extraction of Al from alumuna.Statement -2: It dissilves alumina
Last Answer : Statement -I :Cryolite is used in electrolytic extraction of Al from alumuna. Statement -2: It dissilves alumina
Description : The function of adding cryolite in the electrolytic reduction of alumina by Hall-Heroult process is to
Last Answer : The function of adding cryolite in the electrolytic reduction of alumina by Hall-Heroult ... D. increase the electrical canductivity of alumina
Description : The major role of fluorpar (`CaF_2` ) which added in small quantities in the electrolyte reduction of alumina dissolved in fused cryolite `(N_(3)AlF_(
Last Answer : The major role of fluorpar (`CaF_2` ) which added in small quantities in the electrolyte reduction ... the rate of oxidation of carbon at the anode
Description : (A) Alumina has hgih condutivity (R ) The mixture of alumia and cryolite is used for electrolytic reduction in order to extract aluminium
Last Answer : (A) Alumina has hgih condutivity (R ) The mixture of alumia and cryolite is used for electrolytic reduction ... (A) is incorrect but (R ) is correct
Description : The metallic aluminium is obtained from pure alumina in the presence of fused cryolite by (A) Electrolysis (B) Electrolytic reduction (C) Electrolytic oxidation (D) None of these
Last Answer : (B) Electrolytic reduction
Description : CO2 can be absorbed by (A) Hot cupric oxide (B) Heated charcoal (C) Cold Ca(OH)2 (D) Alumina
Last Answer : (B) Heated charcoal
Last Answer : Cryolite signal na3alf6
Description : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite)` Cathode : fraphite inside Fe -Container Coke power is spreased over the
Last Answer : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite)` Cathode : fraphite inside Fe ... aluminmum by air D. (A) and (B) both
Description : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite) ` Cathode : fraphite inside Fe -Container The purpose of adding cryolite
Last Answer : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite) ` Cathode : fraphite inside ... the impurities as slag D. Both (a) & (B)
Description : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite)` Cathode : fraphite inside Fe -Container Pick out the statement which is
Last Answer : Electrolytic reducation of `Al_(2)O_(3)` Electrolyte `(Al_(2)O_(3)+cryolite)` Cathode : fraphite ... 2)` D. nikkel may be affected at high temperature
Description : Statement -1 In the electltic reduction of `Al_(2)O_(3)`cryolite is used . Statement -2: Cryolite si an ore of aluminium
Last Answer : Statement -1 In the electltic reduction of `Al_(2)O_(3)`cryolite is used . Statement -2: Cryolite si an ore of aluminium
Description : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite rods. Coke powder is spreadded over the molten electro
Last Answer : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite rods. ... of molten aluminium by air D. (a) both (b)
Description : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite rods. The purpose of adding crylite is :
Last Answer : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite rods. ... . to increase melting point of `Al_(2)O_(3)`
Description : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite rods. What is wrong if anode is made of nickel instant
Last Answer : Electrolytic reduction of `Al_(2)O_(3)`. Electrolyte (`Al_(2)O_(3)+"cryolite")` Anode: Graphite ... CO D. Nickel May be affected by high temperature.
Description : The major role of flourspar, `CaF_(2)` which is added in small amount in the electrolytic reduction of `Al_(2)O_(3)` dissolved on fused cryolite in fu
Last Answer : The major role of flourspar, `CaF_(2)` which is added in small amount in the electrolytic reduction ... the rate of oxidation of carbon at the anode
Description : In the elactrolytic extraction of aluminium, cryolite is used.
Last Answer : In the elactrolytic extraction of aluminium, cryolite is used. A. Lower the melting point of ... impurities from alumina D. Minimise the anodic effect
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 : Which one of the following mineral does not contain oxygen? (1) Haematite (2) Bauxite (3) Cryolite (4) Calcite
Last Answer : (3) Cryolite Explanation: Cryolite (Na3AlF6, sodium hexafluoroaluminate) does not contain oxygen. It occurs as glassy, colorless, white-reddish to gray-black prismatic monoclinic crystals. Cryolite is used as an insecticide and a pesticide. It is also used to give fireworks a yellow color.
Description : The important ore of aluminium is – (1) bauxite (2) cryolite (3) fluorspar (4) haematite
Last Answer : (1) bauxite Explanation: Bauxite 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 ... it was first recognized as containing aluminium and named by the French geologist Pierre Berthier in 1821.
Description : What is cryolite? Write its chemical formula.
Last Answer : Cryolite is chemically sodium aluminium fluoride. Its molecular formula is Na3AlF6.
Description : What is the role of molten cryolite in the extraction of aluminium?
Last Answer : When pure alumina is mixed with molten cryolite, it forms an electrolyte at 1223K. Molten cryolite also acts as a solvent for alumina.
Description : Phosphoric acid is prepared from (A) Cryolite (B) Chalcopyrite (C) Rock phosphate (D) None of these
Last Answer : (C) Rock phosphate
Description : Identify the correct statement with reference to the extractive metallurgy of aluminium. (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3 (B) Approximately 80% of ... is immediately vaporised (D) Anode effect sets in when the cryolite concentration goes below 40%.
Last Answer : (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3
Description : The Al2O3 content of cryolite in Hall-Heroult cell is maintained between __________ percent. (A) 2-5 (B) 18-20 (C) 12-15 (D) 6-12
Last Answer : (A) 2-5
Description : Which of the following is not an ore of copper? (A) Cryolite (B) Azurite (C) Chalcopyrite (D) Malachite
Last Answer : Option A
Description : Name the process used to obtain Aluminum by electrolysis of aluminum oxide dissolved in molten cryolite?
Last Answer : ANSWER: HALL PROCESS
Description : Which one of the following mineral does not contain oxygen ? (1) Haematite (2) Bauxite (3) Cryolite (4) Calcite
Last Answer : Cryolite
Description : The important ore of aluminium is (1) bauxite (2) cryolite (3) fluorspar (4) haematite
Last Answer : bauxite
Description : Alumina is an ionic compound but insoluble in water because
Last Answer : Alumina is an ionic compound but insoluble in water because A. its lattice energy is very high B. ... & hydration energy are same D. none of these
Description : The process of converting hydrated Alumina into anhydrous Alumina is called
Last Answer : The process of converting hydrated Alumina into anhydrous Alumina is called A. Roasting B. Smelting C. Dressing D. Calcination
Description : Electrolytic reduction of alumina to aluminum by the Hall-Heroult process is carried out
Last Answer : Electrolytic reduction of alumina to aluminum by the Hall-Heroult process is carried out A. In ... which forms a melt with higher melting temparature.
Description : During electrolytic reduction of alumina , two auxiliary electrolytes X and Y are added to increase the electrical conductance and lower the temperatu
Last Answer : During electrolytic reduction of alumina , two auxiliary electrolytes X and Y are added to increase ... . alum and flourspar D. flourspar and bauxite
Last Answer : The process of converting hydrated Alumina into anhydrous Alumina is called A. roasting B. smelting C. dressing D. calcination
Description : In the elctrolysis of alumina using cryotile, the reaction that takes place at cathode is
Last Answer : In the elctrolysis of alumina using cryotile, the reaction that takes place at cathode is A. `12F^(-) to 6 F_(2)+ ... 2)` D. `4Al^(3+)+12e^(-) to 4Al`
Description : The first Alumina plant in India is situated at (a) Kiriburu (Jharkhand) (b) Ratnagiri (Maharashtra) (c) Sirpur (Andhra Pradesh) (d) Korba (Madhya Pradesh)
Last Answer : Ans: (d)
Description : Frequently employed materials for the adsorption chromatography of proteins include (A) High capacity supporting gel (B) Starch blocks (C) Calcium phosphate gel alumina gel and hydroxy apatite (D) All of these
Last Answer : Answer : C
Description : Which of the following is an absorbent? A.silica gel B. activated alumina C. both of the mentioned D. none of the mentioned
Last Answer : ANSWER : C
Description : The ‘IC’ chips used in computers are made of (a) chromium (b) iron oxide (c) alumina (d) silicon
Description : Slag is a name given for - (1) molten iron (2) molten sand (3) molten alumina (4) molten calcium silicate
Last Answer : (3) molten alumina Explanation: Slag is a partially vitreous byproduct of the process of smelting ore, which separates the desired metal fraction from the unwanted fraction. A good example is steelmaking ... separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
Description : Quartz is a crystalline form of - (1) Alumina (2) Glass (3) Silica (4) Limestone
Last Answer : (3) Silica Explanation: Quartz is made up of a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. Tridymite ... is a denser polymorph of quartz found in some meteorite impact sites and in metamorphic rocks.
Description : Most commonly used rubber vulcanisation agent is (A) Sulphur (B) Bromine (C) Platinum (D) Alumina
Last Answer : (A) Sulphur
Description : Pick out the wrong statement. (A) Lower boiling paraffins have higher octane number than higher paraffins (B) Dehydrogenation of naphthenes to aromatics is a desirable reaction in reforming ... is dearomatised kerosene (D) Catalyst used in catalytic reforming is platinum on silica-alumina base
Last Answer : (C) The most ideal feedstock for thermal reforming is dearomatised kerosene
Description : . Which of the following is used as a catalyst in fluidised bed catalytic cracking? (A) Silica-magnesia (B) Silica-alumina (C) Bentonite clays (D) All (A), (B) and (C
Last Answer : (D) All (A), (B) and (C
Description : Catalyst used in the catalytic cracking is (A) Silica-alumina (B) Silica gel (C) Vanadium pentoxide (D) Nickel
Last Answer : (A) Silica-alumina
Description : Catalyst used in catalytic reforming is (A) Platinum on alumina (B) Nickel (C) Iron (D) Aluminium chloride
Last Answer : (A) Platinum on alumina
Description : Catalyst used in the isomerisation is (A) Aluminium chloride (B) Alumina (C) Nickel (D) Phosphoric acid
Last Answer : (A) Aluminium chloride
Description : Catalyst used in alkylation process is (A) Sulphuric acid (B) Nickel (C) Silica gel (D) Alumina
Last Answer : (A) Sulphuric acid
Description : Which of the following is not used as a surface active agent in a flocculation operation? (A) Sodium silicate (B) Quartz (C) Lime (D) Alumina
Last Answer : (B) Quartz