Calcination isused to convert zinc carbon- ateinto zinc oxide. But cuproussulphate is converted into cuprousoxide by roasting: What happens to the ore when it is subjected to calcination?

Calcination is used to convert zinc carbonate into zinc oxide. But cuprous sulphate is converted into cuprous oxide by roasting: What is the difference between calcination and roasting?

Which of the following statements are wrong? i) Calcination is mainly used for carbonate ore to get its oxide ii) Hydrated ore and hydroxides become anhydrous by calcination iii) Impurities like S, As and Sb are removed in the form of elemental vapours by calcination iv) Roasting is an endothermic process v) Roasting is mainly applicable for sulphide ore to get its oxide vi) Some times as a result of roasting, higher oxidation state oxide gets converted into lower oxidation state oxide.

Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly?