Question

Describe the role of following

a) Iodine in the refining of Zr?

b) Silica in the extraction of Cu?

c) Cryolite in the extraction of Al.​

Answer 1

Answer:

Cryolite reduces the melting point of Al2O3 and increases its electrical conductivity. ... The function of cryolite is to lower the fusion temperature. 3. Zirconium crude metal is heated with iodine in an evacuated vapour to separate from impurities and this decomposes at 1800 K to give a pure zirconium metal and iodine..

. Cryolite reduces the melting point of Al2O3 and increases its electrical conductivity. Aluminium is produced by the electrolytic reduction of fused alumina in the electrolytic cell. Alumina is not an electrolyte. So it is made as an electrolyte by dissolving it in the fused cryolite. The function of cryolite is to lower the fusion temperature. 3. Zirconium crude metal is heated with iodine in an evacuated vapour to separate from impurities and this decomposes at 1800 K to give a pure zirconium metal and iodine. Initially iodine is heated with zirconium to form a volatile compound. 4. Sulphide ores which are concentrated by the froth floatation process. Depressants are used to prevent certain type of particles from forming the froth. NaCN act as a depressant to separate ZnS from PbS.Read more on Sarthaks.com - https://www.sarthaks.com/866703/describe-the-role-of-the-following-in-the-process-mentioned