Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
(a) Name two metals which are found in free state in nature.
(b) What chemical process is used for extracting a metal from its oxide ore?
Name one metal which is extracted by this method.
(c) Describe the extraction of zinc metal from its sulphide ore as well as its carbonate ore. Write equations of all the reactions involved.
(a) The metals that can be found in the free state in nature are gold and silver as Gold, Platinum and Silver are least reactive metals, hence they are found in a free state in nature.
(b) The chemical process which is used for obtaining a metal from its oxide is known as reduction. In this process, metal oxides are reduced to their respective metals by using suitable reducing agents such as carbon or by using some highly reactive metals to displace the metals from their oxides.
Iron is extracted by this method.
$Fe_2O_3 + 2Al \rightarrow Al_2O_3 + 2Fe$
(c) i) Metal sulphides are roasted to obtain metal oxides. Roasting is the process of heating metals sulphides [less than the melting point of metal] to remove sulphur and the metal is converted to metal oxide.
Eg: Zinc sulphide is roasted to form Zinc.
$ZnS + O_2(g) \rightarrow[Heat] ZnO(s) + SO_2(g)$
(ii) Metal carbonates are calcinated to obtain metal oxides. Calcination is the process of heating metal carbonates below the melting point, in limited supply or no supply of oxygen to get metal oxide as a step of purification.
Eg: Zinc carbonate is calcinated to form Zinc oxide which is further reduced to obtain Zinc.
$ZnCO_3(S) \rightarrow{Heat} ZnO(s) + CO_2(g)$
64 Views
