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प्रश्न
What is aqua-regia? Name two special metals which are insoluble in common reagents but dissolve in aqua-regia.
उत्तर
Aqua-regia is a freshly prepared mixture of one part of concentrated nitric acid and three parts of concentrated hydrochloric acid. Gold and platinum are the special metals that are insoluble in common reagents but dissolve in aqua-regia.
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संबंधित प्रश्न
What is meant by refining of a metal? Name the most widely used method for the refining of impure metals obtained by various reduction processes. Describe this method with the help of a labelled diagram by taking the example of any metal.
Explain how the following metals are obtained from their compounds by the reduction process:
(i) Metal M which is in the middle of the reactivity series.
(ii) Metal N which is high up in the reactivity series.
Give one example of each type
Draw a neat labelled diagram.
Hydraulic separation method.
Which of the following process to be carried out to avoid the
formation of greenish layer on brass vessels due to corrosion?
Name one metal each occurring as :
A sulphine
Name one metal each occurring as :
A carbonate
Ionic compounds are electrically _______.
Bauxite is mixed with cryolite so as to
(i) reduce its melting point
(ii) increase its electrical conductivity
(iii) molten cryolite acts as a solvent
(iv) increase its melting point
Reaction between X and Y, forms compound Z. X loses electron and Y gains electron. Which of the following properties is not shown by Z?
A reddish-brown metal ‘X’, when heated in air, gives a black compound ‘Y’, which when heated in the presence of H2 gas gives ‘X’ back. ‘X’ is refined by the process of electrolysis; this refined form of ‘X’ is used in electrical wiring. Identify ‘X’ and ‘Y’. Draw a well-labelled diagram to represent the process of refining ‘X’.