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(i) Why could fluorine not be prepared f...

(i) Why could fluorine not be prepared for a long time from HF and metal fluorides either by electrolysis or by any chemical reaction ?
(ii) Describe the modern method for the preparation of fluorine by giving:
(a) Materials used in the construction of the cell.
(b) Electrolyte used.
(c) Electrode reactions.

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Fluorine could not be prepared for a long time as it is very reactive in nature and reacts with the material of the vessels. Also, the aqueous solution of `H_(2)F_(2)` produced anhydrous HF which is a non conductor of electricity and highly stable making it impossible to be prepared by electrolysis.
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