• question_answer The pair that does NOT require calcination is: A) $ZnO$ and $MgO$ B) $ZnO$ and $F{{e}_{2}}{{O}_{3}}.x{{H}_{2}}O$ C) $ZnC{{O}_{3}}$ and $CaO$ D) $F{{e}_{2}}{{O}_{3}}$and $CaC{{O}_{3}}.MgC{{O}_{3}}$

In calcination the ore is converted to metal oxide. $ZnO$ and $MgO$ are already in oxide form.