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प्रश्न
Why do gold ornaments look new even after several years of use?
उत्तर
Gold is a least reactive metal. It does not react with air, water, acids, alkalis and other gases in the environment. Due to this non-reactive nature, gold metal's shine lasts for years and gold ornaments look new even after several years of use.
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संबंधित प्रश्न
Name one metal which is extracted by reduction with aluminium.
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
Name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae.
An ore of manganese metal is:
(a) bauxite
(b) haematite
(c) cuprite
(d) pyrolusite
The metal which can be extracted from pyrolusite ore is:
(a) mercury
(b) manganese
(c) aluminium
(d) magnesium
Give the principles of electromagnetic separation.
What is meant by refining of metals? Name the three common methods used for refining.
Aluminium oxide is _______ oxide.
Explain the difference between Bayer’s process and Hall’s process by explaining the Bayer’s process.
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Identify the substance oxidised and reduced in the above reaction.
