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Account for the foolowing: (a) Aluminium is not prepared by carrying out the electrolysis of moltent alumina (Al_(2)O_(3)). (b) Aluminium is preferred in electrical cables though it is relatively less conducting than copper. (iii) Aluminium dissolves in both acidic and basic solutions.

Answer» <html><body><p></p>Solution :(a) Alumina `(Al_(2)O_(3))` is a poor <a href="https://interviewquestions.tuteehub.com/tag/conductor-928880" style="font-weight:bold;" target="_blank" title="Click to know more about CONDUCTOR">CONDUCTOR</a> of <a href="https://interviewquestions.tuteehub.com/tag/electricity-968393" style="font-weight:bold;" target="_blank" title="Click to know more about ELECTRICITY">ELECTRICITY</a> and, therefore, the process of electrolysis is not very successful. <a href="https://interviewquestions.tuteehub.com/tag/moreover-563893" style="font-weight:bold;" target="_blank" title="Click to know more about MOREOVER">MOREOVER</a>, the melting point of alumina is also very high (2323K) and it is very difficult to attain and maintain this temperature. Alumina is genrally mixed with cryolite `(Na_(3)AIF_(6))` which lowers the melting point to maintain this temperature. Alumina is generally mixed with cryolite `(Na_(3)AIF_(6))` which lowers the meltingpoint to about 1173k and also converts aluminium oxide to aluminium <a href="https://interviewquestions.tuteehub.com/tag/fluoride-993703" style="font-weight:bold;" target="_blank" title="Click to know more about FLUORIDE">FLUORIDE</a> `(AIF_(3))` which is quite conducting. <br/> (b) Although aluminium is less conducting than copper it is <a href="https://interviewquestions.tuteehub.com/tag/still-653256" style="font-weight:bold;" target="_blank" title="Click to know more about STILL">STILL</a> preferred in the electric cables because it is cheaper than copper. <br/> (c) Aluminium is weakly electrospostive in nature. it, therefore, reacts with both acids and bases <br/> `2Al+6HCLrar2AlCl_(3)+3H_(2)` <br/> `2Al+2NaOH+2H_(2)Orarr2NaAlO_(2)+3H_(2)` <br/>Sod. metaaluminate</body></html>


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