Careers360 Logo
ask-icon
share
    How to Score High in JEE Main 2026 Physics – Tips, Tricks & Important Topics

    Calcination and Roasting - Practice Questions & MCQ

    Edited By admin | Updated on Sep 18, 2023 18:35 AM | #JEE Main

    Quick Facts

    • Conversion of ore into oxide - Calcination and Roasting is considered one the most difficult concept.

    • 38 Questions around this concept.

    Solve by difficulty

    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?

    During the metallurgical process of calcination:

    Calcination is the process of heating the ore:

    JEE Main 2026: January Question Paper with Solutions

    JEE Main 2026 Tools: College Predictor

    JEE Main 2026: Important Formulas | Foreign Universities in India

    Comprehensive Guide: IIT's | NIT'sIIIT's

    Roasting is usually performed in:

    Concepts Covered - 0

    Conversion of ore into oxide - Calcination and Roasting

    Calcination
    Calcination is the process of heating the ores below their melting points in absence of air to remove volatile impurities like water, CO2 and organic
    matter etc.

    For example:

    \mathrm{CaCO}_{3}\: \rightarrow \mathrm{CaO}+\mathrm{CO}_{2} \uparrow
    Limestone        Calcium
                           oxide

    \mathrm{Al}_{2} \mathrm{O}_{3}.\mathrm{H}_{2} \mathrm{O}\: \rightarrow \mathrm{Al}_{2} \mathrm{O}_{3}+2 \mathrm{H}_{2} \mathrm{O} \uparrow
       Bauxite                 Alumina

    During calcination the ore becomes porous, volatile impurities are removed and carbonate ore decomposes into oxides.

    Roasting
    Roasting is the process of heating the ore in excess of air in order to convert metals into their oxides and water-insoluble sulphides into water-soluble sulphates. It is also called de-electronation of ores.

    For example:

    2 \mathrm{FeS}+3 \mathrm{O}_{2}\: \overset{\Delta }{\rightarrow}2 \mathrm{FeO}+2 \mathrm{SO}_{2}
    Pyrite

    2 \mathrm{HgS}+3 \mathrm{O}_{2} \stackrel{\Delta}{\longrightarrow} 2 \mathrm{HgO}+2 \mathrm{SO}_{2}
    Cinnabar

    \mathrm{ZnS\: +\: 2O_{2}\: \overset{\Delta }{\rightarrow}\: ZnSO_{4}}
    Zinc Sulphide

    \mathrm{PbS}+2 \mathrm{O}_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{PbSO}_{4}
    Lead Sulphide

    During roasting volatile impurities are removed, S, As, Sb are removed as SO2, As2O3, Sb2O3 respectively and sulphides ores are converted into their oxides.

    NOTE: Both calcination and roasting occur in a mainly reverberatory furnaces.

    "Stay in the loop. Receive exam news, study resources, and expert advice!"

    Get Answer to all your questions