Q14 of 26 Page 1

A. Name the method of refining Zirconium.

B. In the extraction of Al, impure is dissolved in conc. NaOH to form sodium aluminate and leaving impurities behind. What is the name of this process?


C. What is the function of limestone in the extraction of iron from its oxides?


A. Van Arkel method is used for refining Zirconium or Titanium. In this method oxygen and nitrogen, present as impurity are removed by heating metal in an evacuated vessel with iodine. The metal iodide volatize and it is decomposed on a tungsten filament, heated to about 1800K. The pure metal is deposited on the filament.


B. The name of the process is leeching of alumina


C. Limestone acts as a flux-cleaning agent.


More from this chapter

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12

The rate constant for the first-order decomposition is given by the following equation :


Calculate for this reaction and rate constant k if it's half-life period be 200 minutes. Ea2.303RT


(Given :


13

A. Out of silica gel and anhydrous which will adsorb the water vapours?

B. Out of and which one is more effective in causing coagulation of positively charged sol? Give reason.


C. Out of sulphur sol and proteins, which one forms macromolecular colloids?


 15

Calculate of the following reaction at 298K :


Given :


16

Give reasons :

A. Mn shows the highest oxidation state of +7 with oxygen but with fluorine, it shows the highest oxidation state of +4


B. Zn is soft whereas Cr is hard.


C. is a good reducing agent.