Answer
Verified
280.2k+ views
Hint: A fire brick, also known as a firebrick or refractory, is a ceramic block used to line furnaces, kilns, fireboxes, and fireplaces. The primary purpose of a refractory brick is to endure high temperatures, but it also has a poor thermal conductivity to improve energy efficiency. Dense firebricks are typically employed in applications that are subjected to intense mechanical, chemical, or thermal stresses, such as the inside of a wood-fired kiln or furnace, which is subjected to abrasion from wood, fluxing from ash or slag, and high temperatures.
Complete answer:
The Downs' process is an electrochemical technique for commercially producing metallic magnesium that involves electrolyzing molten \[MgC{{l}_{2}}\] in a specific device known as the Downs cell.
A carbon anode and an iron cathode are used in the Downs cell. Magnesium chloride has been heated to a liquid condition as the electrolyte. Although solid magnesium chloride is a poor conductor of electricity, when it is molten, the magnesium and chloride ions get mobilised and become charge carriers, allowing electric current to be conducted.
Anode \[2C{{l}^{-}}\to \text{ }C{{l}_{2}}\left( g \right)\text{ }+\text{ }2{{e}^{-}}\]
Cathode \[M{{g}^{2+}}+\text{ }2{{e}^{-}}\to \text{ }Mg\text{ }\left( l \right)\]
Overall \[M{{g}^{2+}}+\text{ }2C{{l}^{-}}\to \text{ }Mg\text{ }\left( l \right)\text{ }+\text{ }C{{l}_{2}}\left( g \right)\]
A ceramic substance called firebrick is used to line furnaces and kilns.
Firebrick is heat resistant and has a poor thermal conductivity.
A Downs cell works at 600 degrees Celsius. It is made out of a steel shell with a firebrick lining.
The firebrick has three purposes:
It shields the steel shell from the molten \[NaCl\,(or)\,CaC{{l}_{2}}\]mixture's corrosive effects.
It works as a thermal insulator, trapping heat inside the cell and increasing efficiency.
It functions as a self-sealing membrane. The electrolyte freezes in the gap before it reaches the steel shell because the firebrick is thick enough.
Note:
Calcium chloride, barium and strontium chlorides, and, in certain cases, magnesium fluoride are added to the electrolyte to lower the temperature necessary to maintain the electrolyte liquid. Sodium chloride melts at 801 degrees Celsius (1074 degrees Fahrenheit), while a salt combination comprising 33.2 percent \[MgC{{l}_{2}}\] and 66.8% \[CaC{{l}_{2}}\] may be maintained liquid at temperatures as low as 600 degrees Celsius. When using pure magnesium chloride, a metallic magnesium emulsion forms in the molten \[MgC{{l}_{2}}\], making separation difficult. As a result, a combination of \[MgC{{l}_{2}}\] (42 percent) and \[CaC{{l}_{2}}\] (58 percent) is one possibility.
Complete answer:
The Downs' process is an electrochemical technique for commercially producing metallic magnesium that involves electrolyzing molten \[MgC{{l}_{2}}\] in a specific device known as the Downs cell.
A carbon anode and an iron cathode are used in the Downs cell. Magnesium chloride has been heated to a liquid condition as the electrolyte. Although solid magnesium chloride is a poor conductor of electricity, when it is molten, the magnesium and chloride ions get mobilised and become charge carriers, allowing electric current to be conducted.
Anode \[2C{{l}^{-}}\to \text{ }C{{l}_{2}}\left( g \right)\text{ }+\text{ }2{{e}^{-}}\]
Cathode \[M{{g}^{2+}}+\text{ }2{{e}^{-}}\to \text{ }Mg\text{ }\left( l \right)\]
Overall \[M{{g}^{2+}}+\text{ }2C{{l}^{-}}\to \text{ }Mg\text{ }\left( l \right)\text{ }+\text{ }C{{l}_{2}}\left( g \right)\]
A ceramic substance called firebrick is used to line furnaces and kilns.
Firebrick is heat resistant and has a poor thermal conductivity.
A Downs cell works at 600 degrees Celsius. It is made out of a steel shell with a firebrick lining.
The firebrick has three purposes:
It shields the steel shell from the molten \[NaCl\,(or)\,CaC{{l}_{2}}\]mixture's corrosive effects.
It works as a thermal insulator, trapping heat inside the cell and increasing efficiency.
It functions as a self-sealing membrane. The electrolyte freezes in the gap before it reaches the steel shell because the firebrick is thick enough.
Note:
Calcium chloride, barium and strontium chlorides, and, in certain cases, magnesium fluoride are added to the electrolyte to lower the temperature necessary to maintain the electrolyte liquid. Sodium chloride melts at 801 degrees Celsius (1074 degrees Fahrenheit), while a salt combination comprising 33.2 percent \[MgC{{l}_{2}}\] and 66.8% \[CaC{{l}_{2}}\] may be maintained liquid at temperatures as low as 600 degrees Celsius. When using pure magnesium chloride, a metallic magnesium emulsion forms in the molten \[MgC{{l}_{2}}\], making separation difficult. As a result, a combination of \[MgC{{l}_{2}}\] (42 percent) and \[CaC{{l}_{2}}\] (58 percent) is one possibility.
Recently Updated Pages
Basicity of sulphurous acid and sulphuric acid are
Three beakers labelled as A B and C each containing 25 mL of water were taken A small amount of NaOH anhydrous CuSO4 and NaCl were added to the beakers A B and C respectively It was observed that there was an increase in the temperature of the solutions contained in beakers A and B whereas in case of beaker C the temperature of the solution falls Which one of the following statements isarecorrect i In beakers A and B exothermic process has occurred ii In beakers A and B endothermic process has occurred iii In beaker C exothermic process has occurred iv In beaker C endothermic process has occurred
What is the stopping potential when the metal with class 12 physics JEE_Main
The momentum of a photon is 2 times 10 16gm cmsec Its class 12 physics JEE_Main
How do you arrange NH4 + BF3 H2O C2H2 in increasing class 11 chemistry CBSE
Is H mCT and q mCT the same thing If so which is more class 11 chemistry CBSE
Trending doubts
Assertion CNG is a better fuel than petrol Reason It class 11 chemistry CBSE
How does pressure exerted by solid and a fluid differ class 8 physics CBSE
Number of valence electrons in Chlorine ion are a 16 class 11 chemistry CBSE
What are agricultural practices? Define
What does CNG stand for and why is it considered to class 10 chemistry CBSE
The rate of evaporation depends on a Surface area b class 9 chemistry CBSE
Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE
State whether the following statement is true or false class 11 physics CBSE
A night bird owl can see very well in the night but class 12 physics CBSE