Chemistry
From the list of terms given, choose the most appropriate term to match the given description:
[calcination, roasting, pulverisation, smelting] -
(i) Crushing of the ore into a fine powder.
(ii) Heating of the ore in the absence of air to a high temperature.
Related Questions
Answer the following questions with respect to the electrolytic process – in the extraction of aluminium.
(i) Identify the components of the electrolyte other than pure alumina and the role played by each.
(ii) Explain why powdered coke is sprinkled over the electrolytic mixture.
Identify the term in the following :
'The method used to separate ore from gangue by preferential wetting.'
(i) Name the solution used to react with Bauxite as a first step in obtaining pure aluminium oxide, in the Baeyer's process.
(ii) Write the equation for the reaction where the aluminium oxide for the electrolytic extraction of aluminium is obtained by heating aluminium hydroxide.
(iii) Name the compound added to pure alumina to lower the fusion temperature during the electrolytic reduction of alumina.
(iv) Write the equation for the reaction that occurs at the cathode during the extraction of aluminium by electrolysis.
(v) Explain why it is preferable to use a number of graphite electrodes as anode instead of a single electrode, during the above electrolysis.
Name the following :
(i) An alloy of lead and tin that is used in electrical circuits.
(ii) An ore of zinc containing its sulphide.
(iii) A metal oxide that can be reduced by hydrogen.